5.11. IS-IS Command Reference

5.11.1. Command Hierarchies

  1. Tools Commands (refer to the Tools chapter in the 7705 SAR OAM and Diagnostics Guide)

5.11.1.1. Configuration Commands

config
— router
[no] isis [isis-instance]
[no] area-id area-address
auth-keychain name
authentication-key {authentication-key | hash-key} [hash | hash2]
authentication-type {password | message-digest}
database-export [identifier id] [bgp-ls-identifier bgp-ls-id]
export policy-name [policy-name...(up to 5 max)]
— no export
[no] interface ip-int-name
[no] bfd-enable ipv4
csnp-interval seconds
hello-authentication-key {authentication-key | hash-key} [hash | hash2]
hello-authentication-type {password | message-digest}
interface-type {broadcast | point-to-point}
ipv4-node-sid index index_value
ipv4-node-sid label label_value
ipv6-node-sid index index_value
ipv6-node-sid label label_value
level {1 | 2}
hello-authentication-key {authentication-key | hash-key} [hash | hash2]
hello-authentication-type {password | message-digest}
hello-interval seconds
hello-multiplier multiplier
metric metric
— no metric
[no] passive
priority number
— no priority
level-capability {level-1 | level-2 | level-1/2}
lfa-policy-map route-nh-template template-name
lsp-pacing-interval milliseconds
mesh-group [value | blocked]
— no mesh-group
[no] passive
[no] sid-protection
[no] shutdown
[no] ipv4-routing
ipv6-routing native
level {1 | 2}
auth-keychain name
authentication-key {authentication-key | hash-key} [hash | hash2]
authentication-type {password | message-digest}
external-preference external-preference
preference preference
— no preference
level-capability {level-1 | level-2 | level-1/2}
loopfree-alternate remote-lfa [max-pq-cost value]
loopfree-alternate remote-lfa [max-pq-cost value] ti-lfa [max-sr-frr-labels value]
loopfree-alternate ti-lfa [max-sr-frr-labels value]
loopfree-alternate-exclude prefix-policy prefix-policy [prefix-policy...(up to 5 max)]
lsp-lifetime seconds
lsp-mtu-size size
— no lsp-mtu-size
[no] multicast-import [ipv4]
overload [timeout seconds]
— no overload
overload-on-boot [timeout seconds]
reference-bandwidth bandwidth-in-kbps
reference-bandwidth [tbps Tera-bps] [gbps Giga-bps] [mbps Mega-bps] [kbps Kilo-bps]
[no] rsvp-shortcut
adj-sid-hold seconds
entropy-label {force-disable | enable}
[no] shutdown
sid-map node-sid {index value [range value]} prefix {ip address/mask} | ip-address netmask} [set-flags {s}] [level {1 | 2 | 1/2}]
prefix-sid-range global
prefix-sid-range start-label label-value max-index index-value
[no] shutdown
tunnel-mtu bytes
— no tunnel-mtu
tunnel-table-pref preference
[no] shutdown
summary-address {ip-prefix/prefix-length | ip-prefix [netmask]} level
— no summary-address {ip-prefix/prefix-length | ip-prefix [netmask]}
[no] timers
lsp-wait lsp-wait [lsp-initial-wait initial-wait] [lsp-second-wait second-wait]
no lsp-wait
spf-wait spf-wait [spf-initial-wait initial-wait] [spf-second-wait second-wait]
— no spf-wait
[no] unicast-import-disable [ipv4]

5.11.1.2. Show Commands

show
— router
isis all
isis [isis-instance]
adjacency [ip-int-name | ip-address | nbr-system-id] [detail]
capabilities [system-id | lsp-id] [level level]]
database [system-id | lsp-id] [detail] [level level]
interface [ip-int-name | ip-address] [detail]
mapping-server [prefix ip-address [/mask]] [index index] [level level] [flag {s}]
prefix-sids [ipv4-unicast | ipv6-unicast | mt mt-id-number] [ip-prefix[/prefix-length]] [sid sid] [adv-router {system-id | hostname}] [srms | no-srms]
routes [ipv4-unicast | ipv6-unicast | mt mt-id-number] [ip-prefix[/prefix-length]] [alternative] [exclude-shortcut] [detail]
spf-log [detail]
status
summary-address [ip-prefix[/prefix-length]]
topology [detail] [lfa]

5.11.1.3. Clear Commands

clear
— router
isis [isis-instance]
adjacency [system-id]
database [system-id]
export

5.11.1.4. Debug Commands

debug
— router
isis [isis-instance]
[no] adjacency [ip-int-name | ip-address | nbr-system-id]
[no] cspf
interface [ip-int-name | ip-address]
— no interface
leak [ip-address]
— no leak
[no] lsdb [level-number] [system-id | lsp-id]
[no] misc
packet [packet-type] [ip-int-name | ip-address | ipv6-address] [detail]
— no packet
rtm [ip-address]
— no rtm
[no] spf [level-number] [system-id]

5.11.1.5. Monitor Commands

monitor
— router
isis [isis-instance]
statistics [interval seconds] [repeat repeat] [absolute | rate]

5.11.2. Command Descriptions

5.11.2.1. Configuration Commands

5.11.2.1.1. Generic Commands

shutdown

Syntax 
[no] shutdown
Context 
config>router>isis
config>router>isis>segment-routing
config>router>isis>segment-routing>mapping-server
config>router>isis>interface
Description 

This command administratively disables the entity. When disabled, an entity does not change, reset, or remove any configuration settings or statistics. Many entities must be explicitly enabled using the no shutdown command.

The operational state of the entity is disabled as well as the operational state of any entities contained within. Many objects must be shut down before they can be deleted.

Unlike other commands and parameters where the default state is not indicated in the configuration file, shutdown and no shutdown are always indicated in system-generated configuration files.

The no form of the command puts an entity into the administratively enabled state.

Default 

IS-IS Global - the IS-IS protocol is created in the no shutdown state

IS-IS Interface - when an IP interface is configured as an IS-IS interface, IS-IS on the interface is in the no shutdown state by default

5.11.2.1.2. Global Commands

isis

Syntax 
[no] isis [isis-instance]
Context 
config>router
Description 

This command activates an IS-IS instance on the router and enables access to the context to define IS-IS parameters.

Instance 0, the base instance, is enabled when the isis command is run without specifying an isis-instance. Multiple IS-IS instances are enabled by including an isis-instance value.

The no form of the command deletes the IS-IS instance and removes all configuration parameters.

Default 

no isis

Parameters 
isis-instance—
the IS-IS instance ID. If no isis-instance is specified, instance 0 is used.
Values—
1 to 31

 

advertise-router-capability

Syntax 
advertise-router-capability {area | as}
no advertise-router-capability
Context 
config>router>isis
Description 

This command enables advertisement of a router’s capabilities to its neighbors for informational and troubleshooting purposes. A TLV as defined in RFC 4971 advertises the TE Node Capability Descriptor capability.

The parameters (area and as) control the scope of the capability advertisements.

The no form of this command disables this capability.

Default 

no advertise-router-capability

Parameters 
area—
capabilities are only advertised within the area of origin
as—
capabilities are advertised throughout the entire autonomous system

advertise-tunnel-link

Syntax 
[no] advertise-tunnel-link
Context 
config>router>isis
Description 

This command enables the forwarding adjacency feature. With this feature, IS-IS advertises an RSVP-TE LSP as a link so that other routers in the network can include it in their SPF calculations. The RSVP-TE LSP is advertised as an unnumbered point-to-point link and the link-state PDU (LSP) has no traffic engineering opaque sub-TLVs as per RFC 3906.

The forwarding adjacency feature can be enabled independently from the IGP shortcut feature (rsvp-shortcut). If both features are enabled for a given IS-IS instance, the forwarding adjacency feature takes precedence.

When this feature is enabled, each node advertises a point-to-point unnumbered link for each best-metric tunnel to the router ID of any endpoint node. The node does not include the tunnels as IGP shortcuts in the SPF calculation directly. Instead, when the LSP advertising the corresponding point-to-point unnumbered link is installed in the local routing database, the node performs an SPF calculation using the link like any other link LSP.

The link bidirectional check requires that a regular link or tunnel link exists in the reverse direction for the tunnel to be used in the SPF calculation.

An RSVP-TE LSP can be excluded from being used as a forwarding adjacency with the config>router>mpls>lsp>no igp-shortcut command.

The no form of this command disables forwarding adjacency and therefore disables the advertisement of RSVP-TE LSPs into IS-IS.

Default 

no advertise-tunnel-link

area-id

Syntax 
[no] area-id area-address
Context 
config>router>isis
Description 

This command configures the area ID portion of the Network Service Access Point (NSAP) address, which identifies a point of connection to the network, such as a router interface.

Addresses in the IS-IS protocol are based on the ISO NSAP addresses and Network Entity Titles (NETs), not IP addresses. NET addresses are constructed similarly to NSAPs with the exception that the selector ID is always 00. NET addresses are exchanged in Hello and LSP PDUs. All NET addresses configured on the node are advertised to its neighbors.

Up to three area addresses can be configured.

NSAP addresses are divided into three parts. Only the area ID portion is configurable:

  1. area ID – a variable-length field between 1 and 13 bytes that identifies the area to which the router belongs. This field includes the Authority and Format Identifier (AFI) as the first (most significant) byte and the area identifier.
  2. system ID – A 6-byte system identifier. This value is not configurable. The system ID is derived from the system or router ID and uniquely identifies the router.
  3. selector ID – A 1-byte selector identifier that is always 00 for an NET. This value is not configurable.

For level 1 interfaces, neighbors can have different area IDs, but they must have at least one area ID (AFI + area) in common. Sharing a common area ID, they become neighbors and area merging between the potentially different areas can occur.

For level 2 interfaces, neighbors can have different area IDs. However, if they have no area IDs in common, they become only level 2 neighbors and only level 2 LSPs are exchanged.

For level 1/2 interfaces, neighbors can have different area IDs. If they have at least one area ID (AFI + area) in common, they become neighbors. In addition to exchanging level 2 LSPs, area merging between potentially different areas can occur.

If multiple area-id commands are entered, the system ID of all subsequent entries must match the system ID of the first area address.

The no form of the command removes the area address.

Default 

n/a — no area address is assigned

Parameters 
area-address—
the area ID, from 1 to 13 bytes (if fewer than 13 bytes are entered, the rest of the field is padded with zeros)

auth-keychain

Syntax 
auth-keychain name
no auth-keychain
Context 
config>router>isis
config>router>isis>level
Description 

This command associates an authentication keychain with the IS-IS instance or level. The keychain is a collection of keys used to authenticate IS-IS messages from remote peers. The keychain allows the rollover of authentication keys during the lifetime of a session and also supports stronger authentication algorithms than clear text and MD5.

The keychain must already be defined in the config>system>security>keychain context.

Either the authentication-key command or the auth-keychain command can be used by IS-IS, but both cannot be supported at the same time. If both commands are configured, the auth-keychain configuration will be applied and the authentication-key command will be ignored.

By default, authentication is not enabled.

Default 

no auth-keychain

Parameters 
name—
the name of an existing keychain, up to 32 characters

authentication-check

Syntax 
[no] authentication-check
Context 
config>router>isis
Description 

This command sets an authentication check to reject PDUs that do not match the type or key requirements.

The default behavior when authentication is configured is to reject all IS-IS protocol PDUs that have a mismatch in either the authentication type or authentication key.

When no authentication-check is configured, authentication PDUs are generated and IS-IS PDUs are authenticated on receipt. However, although mismatches cause an event to be generated, the mismatches will not be rejected.

Default 

authentication-check

authentication-key

Syntax 
authentication-key {authentication-key | hash-key} [hash | hash2]
no authentication-key
Context 
config>router>isis
config>router>isis>level
Description 

This command sets the authentication key used to verify PDUs sent by neighboring routers on the interface. Neighboring routers use passwords to authenticate PDUs sent from an interface. For authentication to work, both the authentication key and the authentication type on a segment must match. The authentication-type command must also be entered.

To configure authentication on the global level, configure this command in the config>router>isis context. When this parameter is configured on the global level, all PDUs are authenticated, including the Hello PDU.

To override the global setting for a specific level, configure the authentication-key command in the config>router>isis>level context. When configured within the specific level, Hello PDUs are not authenticated.

By default, no authentication key is configured.

Either the authentication-key command or the auth-keychain command can be used by IS-IS, but both cannot be supported at the same time. If both commands are configured, the auth-keychain configuration will be applied and the authentication-key command will be ignored.

The no form of the command removes the authentication key.

Default 

no authentication-key

Parameters 
authentication-key—
the authentication key can be any combination of ASCII characters up to 254 characters in length (unencrypted). If spaces are used in the string, the entire string must be enclosed in double quotes (“ ”).
hash-key—
the hash key can be any combination of ASCII characters up to 352 characters in length (encrypted) or 407 characters in length (if the hash2 parameter is used). If spaces are used in the string, the entire string must be enclosed in double quotes (“ ”).

This is useful when a user must configure the parameter, but for security purposes, the actual unencrypted key value is not provided.

hash—
specifies that the key is entered in an encrypted form. If the hash parameter is not used, the key is assumed to be in a non-encrypted, clear text form. For security, all keys are stored in encrypted form in the configuration file with the hash parameter specified.
hash2—
specifies that the key is entered in a more complex encrypted form. If the hash2 parameter is not used, the less encrypted hash form is assumed.

authentication-type

Syntax 
authentication-type {password | message-digest}
no authentication-type
Context 
config>router>isis
config>router>isis>level
Description 

This command enables either simple password or message-digest authentication in the global IS-IS or IS-IS level context. Both the authentication key and the authentication type on a segment must match. The authentication-key command must also be entered.

Configure the authentication type at the global level in the config>router>isis context. Configure or override the global setting by configuring the authentication type in the config>router>isis>level context.

The no form of the command disables authentication.

Default 

no authentication-type

Parameters 
password—
enables simple password (plain text) authentication. If authentication is enabled and no authentication type is specified in the command, simple password authentication is enabled.
message-digest—
enables message-digest MD5 authentication in accordance with RFC 1321. If this option is configured, at least one message-digest-key must be configured.

csnp-authentication

Syntax 
[no] csnp-authentication
Context 
config>router>isis
config>router>isis>level
Description 

This command enables authentication of individual IS-IS packets of complete sequence number PDUs (CSNPs).

The no form of the command suppresses authentication of CSNP packets.

Default 

csnp-authentication

database-export

Syntax 
database-export [identifier id] [bgp-ls-identifier bgp-ls-id]
no database-export
Context 
config>router>isis
Description 

This command enables the population of the extended TE database (TE-DB) with the link-state information from the IS-IS instance.

The extended TE-DB is used as a central point for importing all link-state, link, node, and prefix information from IGP instances on the router and exporting the information to BGP-LS on the router. This information includes the IGP, TE, SID sub-TLV, and adjacency SID sub-TLV.

The no form of this command disables database exportation.

Default 

no database-export

Parameters 
identifier—
uniquely identifies the IGP instance in the BGP-LS NLRI when a router has interfaces participating in multiple IGP instances. This parameter defaults to the IGP instance ID assigned by the 7705 SAR. However, because the concept of instance ID defined in IS-IS (RFC 6822) is unique within a routing domain while the one specified for OSPF is significant for the local subnet only (RFC 6549), the user can remove any overlap by configuring the new identifier value to be unique within a particular IGP domain when this router sends the IGP link-state information using BGP-LS.
id—
specifies an entry ID to export
Values—
0 to 18446744073709551615

 

bgp-ls-identifier—
used with the Autonomous System Number (ASN) to correlate the BGP-LS NLRI advertisements of multiple BGP-LS speakers in the same IGP domain. If an NRC-P network domain has multiple IGP domains, BGP-LS speakers in each IGP domain must be configured with the same unique tuple {bgp-ls-identifier, asn}.

The BGP-LS identifier is optional and is only sent in a BGP-LS NLRI if configured in the IGP instance of an IGP domain.

If this IGP instance participates in traffic engineering with RSVP-TE or SR-TE, the traffic-engineering option is not strictly required because enabling the extended TE-DB populates this information automatically. However, it is recommended that the user enable traffic engineering to make the configuration consistent with other routers in the network that do not require enabling of the extended TE-DB.

bgp-ls-id—
specifies a BGP LS ID to export
Values—
0 to 4294967295

 

disable-ldp-sync

Syntax 
[no] disable-ldp-sync
Context 
config>router>isis
Description 

This command disables the IGP-LDP synchronization feature on all interfaces participating in the OSPF or IS-IS routing protocol. When this command is executed, the IGP immediately advertises the actual value of the link cost for all interfaces that have the IGP-LDP synchronization enabled if the currently advertised cost is different. IGP-LDP synchronization will then be disabled for all interfaces. This command does not delete the interface configuration.

The no form of this command restores the default settings and re-enables IGP-LDP synchronization on all interfaces participating in the OSPF or IS-IS routing protocol and for which the ldp-sync-timer is configured (refer to the 7705 SAR Router Configuration Guide for information on configuring the ldp-sync-timer).

Default 

no disable-ldp-sync

entropy-label

Syntax 
entropy-label
Context 
config>router>isis
Description 

This command enables the context for the configuration of entropy label capabilities (ELC) for the routing protocol.

override-tunnel-elc

Syntax 
[no] override-tunnel-elc
Context 
config>router>isis>entropy-label
Description 

This command configures the ability to override any received entropy label capability advertisements. When enabled, the system assumes that all nodes for an IGP domain are capable of receiving and processing the entropy label on segment routed tunnels. This command can only be configured if entropy-label is enabled via the config>router>isis>segment-routing>entropy-label command.

The no version of this command disables the override. The system assumes entropy label capability for other nodes in the IGP instance if capability advertisements are received.

Default 

no override-tunnel-elc

export

Syntax 
export policy-name [policy-name…(up to 5 max)]
no export
Context 
config>router>isis
Description 

This command associates export route policies to determine which routes are exported from the route table to IS-IS.

If no export policy is specified, non-IS-IS routes are not exported from the routing table manager to IS-IS.

If multiple policy names are specified, the policies are evaluated in the order they are specified. The first policy that matches is applied. If multiple export commands are issued, the last command entered will override the previous command. A maximum of five policy names can be specified.

The no form of the command removes all policies from the configuration.

Refer to the 7705 SAR Router Configuration Guide for information on defining route policies.

Default 

n/a — no export route policies specified

Parameters 
policy-name—
the export route policy name. Allowed values are any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.

The specified names must already be defined.

hello-authentication

Syntax 
[no] hello-authentication
Context 
config>router>isis
config>router>isis>interface
Description 

This command enables authentication of individual IS-IS Hello PDUs.

The no form of the command suppresses authentication of Hello PDUs.

Default 

hello-authentication

ignore-attached-bit

Syntax 
[no] ignore-attached-bit
Context 
config>router>isis
Description 

This command specifies that this level 1 router will ignore the attached (ATT) bit in received level 1 link-state PDUs (LSPs) and therefore will not install the default route to the level 1/2 router that set the ATT bit.

The no form of the command specifies that the router will install the default route to the closest level 1/2 router.

Default 

no ignore-attached-bit

ignore-lsp-errors

Syntax 
[no] ignore-lsp-errors
Context 
config>router>isis
Description 

This command specifies that the router will ignore LSPs with internal checksum errors rather than purging the LSPs.

The no form of the command specifies that LSPs with internal checksum errors will be purged, which will cause the originator to resend the LSPs.

Default 

no ignore-lsp-errors

iid-tlv-enable

Syntax 
[no] iid-tlv-enable
Context 
config>router>isis
Description 

This command specifies whether the Instance Identifier (IID) TLV is enabled or disabled for this IS-IS instance so an interface can be used in multiple IS-IS instances.

When enabled, each IS-IS instance marks its packets with the IID TLV containing its unique 16-bit IID for the routing domain. You must use a shutdown/no shutdown command sequence on the IS-IS instance to make the change operational.

The no form of the command disables the IID TLV marking of packets.

Default 

no iid-tlv-enable

ipv4-routing

Syntax 
[no] ipv4-routing
Context 
config>router>isis
Description 

This command enables or disables IPv4 routing on the IS-IS instance.

Default 

ipv4-routing

ipv6-routing

Syntax 
ipv6-routing native
no ipv6-routing
Context 
config>router>isis
Description 

This command enables or disables single topology (native) IPv6 routing on the IS-IS instance. In native mode, IPv6 routing information is exchanged within IS-IS using IS-IS IPv6 TLVs.

Default 

no ipv6-routing

Parameters 
native—
specifies to use IS-IS IPv6 TLVs for IPv6 routing

level

Syntax 
level {1 | 2}
Context 
config>router>isis
config>router>isis>interface
Description 

This command enables the context to configure IS-IS level 1 or level 2 area attributes.

To reset global and/or interface level parameters to the default, the following commands must be entered independently:

— level> no hello-authentication-key
— level> no hello-authentication-type
— level> no hello-interval
— level> no hello-multiplier
— level> no metric
— level> no passive
— level> no priority
Default 

level 1 or level 2

Special Cases 
Global IS-IS Level—
the config>router>isis context configures default global parameters for both level 1 and level 2 interfaces
IS-IS Interface Level—
the config>router>isis>interface context configures IS-IS operational characteristics of the interfaces at level 1 and/or level 2. A logical interface can be configured on one level 1 and one level 2 interface. In this case, each level can be configured independently and parameters must be removed independently.
Parameters 
1—
specifies that the router or interface is a level 1 router or interface
2—
specifies that the router or interface is a level 2 router or interface

external-preference

Syntax 
external-preference external-preference
no external-preference
Context 
config>router>isis>level
Description 

This command configures the preference for IS-IS external routes for the IS-IS level. The preference for internal routes is set with the preference command.

The command configures the preference level for either level 1 or level 2 external routes. The default preferences are listed in Table 63.

A route can be learned by the router from different protocols, in which case, the costs are not comparable. When this occurs, the preference is used to decide which route will be used.

Different protocols should not be configured with the same preference. If this occurs, the tiebreaker is based on the default preferences as listed in Table 63.

Table 63:  Route Preference Defaults by Route Type 

Route Type

Preference

Configurable

Direct attached

0

No

Static routes

5

Yes

OSPF internal

10

Yes

IS-IS level 1 internal

15

Yes

IS-IS level 2 internal

18

Yes

OSPF external

150

Yes

IS-IS level 1 external

160

Yes

IS-IS level 2 external

165

Yes

If multiple routes are learned with an identical preference using the same protocol, the lowest-cost route is used. If multiple routes are learned with an identical preference using the same protocol and the costs (metrics) are equal, the decision of which route to use is determined by the configuration of ECMP in the config>router context. Refer to the 7705 SAR Router Configuration Guide for information on ECMP.

Note:

To configure a preference for static routes, use the config>router>static-route-entry context. Refer to the 7705 SAR Router Configuration Guide for information.

The no form of the command reverts to the default value.

Default 

external-preference 160 — for IS-IS level 1 external routes

external-preference 165 — for IS-IS level 2 external routes

Parameters 
external-preference—
the preference for external routes at this level, expressed as a decimal integer
Values—
1 to 255

 

loopfree-alternate-exclude

Syntax 
[no] loopfree-alternate-exclude
Context 
config>router>isis>level
config>router>isis>interface
Description 

This command instructs IS-IS to exclude a specific interface or all interfaces participating in a specific IS-IS level from the LFA SPF calculation. The LFA SPF calculation can therefore be run only where it is needed.

If an interface is excluded from the LFA SPF in IS-IS, it is excluded in both level 1 and level 2.

Default 

no loopfree-alternate-exclude

preference

Syntax 
preference preference
no preference
Context 
config>router>isis>level
Description 

This command configures the preference for IS-IS level 1 or level 2 internal routes.

A route can be learned by the router from different protocols, in which case, the costs are not comparable. When this occurs, the preference is used to decide which route will be used.

Different protocols should not be configured with the same preference. If this occurs, the tiebreaker is based on the default preferences as listed in Table 63. If multiple routes are learned with an identical preference using the same protocol and the costs (metrics) are equal, the decision of which route to use is determined by the configuration of ECMP in the config>router context. Refer to the 7705 SAR Router Configuration Guide for information on ECMP.

The no form of the command reverts to the default value.

Default 

preference 15 — for IS-IS level 1 internal routes

preference 18 — for IS-IS level 2 internal routes

Parameters 
preference—
the preference for internal routes expressed as a decimal integer
Values—
1 to 255

 

wide-metrics-only

Syntax 
[no] wide-metrics-only
Context 
config>router>isis>level
Description 

This command enables the exclusive use of wide metrics in the LSPs for the level number. Narrow metrics can have values between 1 and 63. IS-IS can generate two TLVs, one for the adjacency and one for the IP prefix. In order to support traffic engineering, wider metrics are required. When wide metrics are used, a second pair of TLVs are added for the adjacency and the IP prefix.

By default, both sets of TLVs are generated. When wide-metrics-only is configured, IS-IS only generates the pair of TLVs with wide metrics for that level.

The no form of the command reverts to the default value.

Default 

no wide-metrics-only

level-capability

Syntax 
level-capability {level-1 | level-2 | level-1/2}
no level-capability
Context 
config>router>isis
config>router>isis>interface
Description 

This command configures the routing level for the IS-IS instance.

An IS-IS router and IS-IS interface can operate at level 1, level 2, or both level 1 and level 2.

A level 1 adjacency can be established if there is at least one area address shared by this router and a neighbor. A level 2 adjacency cannot be established over this interface.

A level 1/2 adjacency is created if the neighbor is also configured as a level 1/2 router and has at least one area address in common. A level 2 adjacency is established if there are no common area IDs.

A level 2 adjacency is established if another router is configured as a level 2 or level 1/2 router with interfaces configured as level 1/2 or level 2. Level 1 adjacencies will not established over this interface.

Table 64 lists capability combinations and the potential adjacencies that can be formed.

Table 64:  Potential Adjacency Capabilities 

Global Level

Interface Level

Potential Adjacency

Level 1/2

Level 1/2

Level 1 and/or level 2

Level 1/2

Level 1

Level 1 only

Level 1/2

Level 2

Level 2 only

Level 2

Level 1/2

Level 2 only

Level 2

Level 2

Level 2 only

Level 2

Level 1

None

Level 1

Level 1/2

Level 1 only

Level 1

Level 2

None

Level 1

Level 1

Level 1 only

The no form of the command removes the level capability from the configuration.

Default 

level-1/2

Special Cases 
IS-IS Router—
in the config>router>isis context, changing the level capability performs a restart on the IS-IS protocol instance
IS-IS Interface—
in the config>router>isis>interface context, changing the level capability performs a restart of IS-IS on the interface
Parameters 
level-1—
specifies that the router or interface can operate at level 1 only
level-2—
specifies that the router or interface can operate at level 2 only
level-1/2—
specifies that the router or interface can operate at both level 1 and level 2

loopfree-alternate

Syntax 
loopfree-alternate
loopfree-alternate remote-lfa [max-pq-cost value]
loopfree-alternate remote-lfa [max-pq-cost value] ti-lfa [max-sr-frr-labels value]
loopfree-alternate ti-lfa [max-sr-frr-labels value]
no loopfree-alternate
Context 
config>router>isis
Description 

This command enables Loop-Free Alternate (LFA) computation by SPF for the IS-IS routing protocol.

When this command is enabled, it instructs the IGP SPF to attempt to precompute both a primary next hop and an LFA backup next hop for every learned prefix. When found, the LFA next hop is populated into the routing table along with the primary next hop for the prefix.

The user enables the remote LFA next-hop calculation by the IGP LFA SPF by using the remote-lfa option. When this option is enabled in an IGP instance, SPF performs the additional remote LFA computation that follows the regular LFA next-hop calculation when the latter calculation results in no protection for one or more prefixes that resolve to a particular interface.

Remote LFA extends the protection coverage of LFA-FRR to any topology by automatically computing and establishing or tearing-down shortcut tunnels, also referred to as repair tunnels, to a remote LFA node that puts the packets back into the shortest path without looping them back to the node that forwarded them over the repair tunnel. The remote LFA node is referred to as a PQ node. A repair tunnel can, in theory, be an RSVP-TE LSP, an LDP-in-LDP tunnel, or a segment routing (SR) tunnel. In this command, remote-lfa is restricted to using an SR repair tunnel to the remote LFA node.

The remote LFA algorithm is a per-link LFA SPF calculation and not a per-prefix calculation like the regular LFA algorithm. The remote LFA algorithm provides protection for all destination prefixes that share the protected link by using the neighbor on the other side of the protected link as a proxy for all the destinations.

The Topology-independent LFA (TI-LFA) further improves the protection coverage of a network topology by computing and automatically instantiating a repair tunnel to a Q node that is not in the shortest path from the computing node. The repair tunnel uses the shortest path to the P node and a source-routed path from the P node to the Q node.

The TI-LFA repair tunnel can have a maximum of three labels pushed in addition to the label of the destination node or prefix. The user can set a lower maximum value for the additional FRR labels by configuring the max-sr-frr-labels option. The default value is 2.

The no form of this command disables the LFA computation by the IGP SPF.

Default 

no loopfree-alternate

Parameters 
remote-lfa—
enables the remote LFA next-hop calculation by the IGP LFA SPF
max-pq-cost value—
specifies the integer used to limit the search of candidate P and Q nodes in remote LFA algorithm by setting the maximum IGP cost from the router performing the remote LFA calculation to the candidate P or Q node
Values—
0 to 4294967295

 

Default—
4261412864
ti-lfa—
enables the use of the topology-independent LFA algorithm in the LFA SPFcalculation
max-sr-frr-labels value
specifies the maximum number of labels that the TI-LFA backup next hop can use. The TI-LFA algorithm uses this value to limit the search for the Q node from the P node on the post-convergence path.
Values—
0 to 3

 

Default—
2

loopfree-alternate-exclude

Syntax 
loopfree-alternate-exclude prefix-policy prefix-policy [prefix-policy...(up to 5 max)]
no loopfree-alternate-exclude
Context 
config>router>isis
Description 

This command excludes from the LFA SPF calculation any prefixes that match a prefix entry in a prefix policy. If a prefix is excluded, it is not included in the LFA SPF calculation, regardless of its priority. Prefix policies are created with the command config>router> policy-options>prefix-list (for information on prefix lists, refer to the 7705 SAR Router Configuration Guide, “Route Policies”).

The default action of the loopfree-alternate-exclude command, when not explicitly specified in the prefix policy, is to “reject”. Therefore, even if the default-action reject statement was not explicitly stated for the prefix policy, a prefix that does not match any entry in the policy will be used in the LFA SPF calculation.

The no form of the command deletes the excluded prefix policy.

Default 

no loopfree-alternate-exclude

Parameters 
prefix-policy—
the name of an existing prefix policy

lsp-lifetime

Syntax 
lsp-lifetime seconds
no lsp-lifetime
Context 
config>router>isis
Description 

This command sets the time interval for LSPs originated by the router to be considered valid by other routers in the domain.

Each LSP received is maintained in an LSP database until the LSP lifetime expires, unless the originating router refreshes the LSP. Each router refreshes its LSPs at the half-life of the lsp-lifetime value (by default, every 10 min (600 s)), so that other routers will not age out the LSP.

The no form of the command reverts to the default value.

Default 

1200

Parameters 
seconds—
the interval for LSPs originated by the route to be considered valid by other routers in the domain
Values—
350 to 65335

 

lsp-mtu-size

Syntax 
lsp-mtu-size size
no lsp-mtu
Context 
config>router>isis
Description 

This command configures the LSP MTU size. If the MTU size is changed from the default value using the CLI or SNMP, IS-IS must be restarted in order for the change to take effect. This can be done by performing a shutdown command and then a no shutdown command in the config>router>isis context.

Note:

If the MTU size is changed from the default value by using the exec command to execute a configuration file with the changed value, IS-IS will automatically bounce before the change takes effect.

The no form of the command reverts to the default value.

Default 

1492

Parameters 
size—
the LSP MTU size
Values—
490 to 9702

 

multicast-import

Syntax 
[no] multicast-import [ipv4]
Context 
config>router>isis
Description 

This command enables the submission of routes into the multicast Route Table Manager (RTM) by IS-IS.

The no form of the command disables the submission of routes into the multicast RTM.

Default 

no multicast-import ipv4

overload

Syntax 
overload [timeout seconds]
no overload
Context 
config>router>isis
Description 

This command administratively sets the IS-IS router to operate in the overload state for a specific time period, in seconds, or indefinitely.

During normal operation, the router may be forced to enter an overload state due to a lack of resources. When in the overload state, the router is only used if the destination is reachable by the router and will not be used for other transit traffic.

If a time period is specified, the overload state persists for the configured length of time. If no time is specified, the overload state operation is maintained indefinitely.

The overload command can be useful in circumstances where the router is overloaded or used prior to executing a shutdown command to divert traffic around the router.

The no form of the command causes the router to exit the overload state.

Default 

no overload

Parameters 
seconds—
the number of seconds that the router remains in the overload state
Values—
60 to 1800

 

Default—
infinity (overload state maintained indefinitely)

overload-on-boot

Syntax 
overload-on-boot [timeout seconds]
no overload-on-boot
Context 
config>router>isis
Description 

This command configures IS-IS in the overload state upon boot-up until one of the following events occurs:

  1. the timeout timer expires
  2. the current overload state is manually overridden with the no overload command

When the router is in an overload state, the router is used only if there is no other router to reach the destination.

The no overload command does not affect the overload-on-boot function. If the overload state is cleared with the no overload command, the router will still re-enter the overload state after rebooting.

If no timeout is specified, IS-IS will go into the overload state indefinitely after a reboot. After the reboot, the IS-IS status will display a permanent overload state:

  1. L1 LSDB Overload : Manual on boot (Indefinitely in overload)
  2. L2 LSDB Overload : Manual on boot (Indefinitely in overload)

This state can be cleared with the no overload command.

If a timeout value is specified, IS-IS will go into the overload state for the configured timeout after a reboot. After the reboot, the IS-IS status will display the remaining time that the system stays in overload:

  1. L1 LSDB Overload : Manual on boot (Overload Time Left : 17)
  2. L2 LSDB Overload : Manual on boot (Overload Time Left : 17)

The overload state can be cleared before the timeout expires with the no overload command.

The no form of the command removes the overload-on-boot functionality from the configuration.

Default 

no overload-on-boot

Parameters 
seconds—
the number of seconds that the router remains in the overload state after rebooting
Values—
60 to 1800

 

Default—
60

poi-tlv-enable

Syntax 
[no] poi-tlv-enable
Context 
config>router>isis
Description 

This command enables the use of the Purge Originator Identification (POI) TLV for this IS-IS instance. The POI is added to purges and contains the system ID of the router that generated the purge, which simplifies troubleshooting and determining what caused the purge.The no form of this command removes the POI functionality from the configuration.

Default 

no poi-tlv-enable

psnp-authentication

Syntax 
[no] psnp-authentication
Context 
config>router>isis
config>router>isis>level
Description 

This command enables authentication of individual IS-IS packets of partial sequence number PDUs (PSNPs).

The no form of the command suppresses authentication of PSNP packets.

Default 

psnp-authentication

reference-bandwidth

Syntax 
reference-bandwidth bandwidth-in-kbps
reference-bandwidth [tbps Tera-bps] [gbps Giga-bps] [mbps Mega-bps] [kbps Kilo-bps]
no reference-bandwidth
Context 
config>router>isis
Description 

This command configures the reference bandwidth used to calculate the default costs of interfaces based on their underlying link speed.

The default interface cost is calculated as follows:

cost = reference bandwidth/bandwidth

If the reference bandwidth is configured as 10 Gbytes (10 000 000 000), a 100 Mb/s interface has a default metric of 100. In order for metrics in excess of 63 to be configured, wide metrics must be deployed (see the wide-metrics-only command).

If the reference bandwidth is not configured, all interfaces have a default metric of 10.

The no form of the command resets the reference bandwidth to the default value.

Default 

no reference-bandwidth (all interfaces have a metric of 10)

Parameters 
bandwidth-in-kbps—
the reference bandwidth in kilobits per second, expressed as a decimal integer
Values—
1 to 400000000

 

Tera-bps
the reference bandwidth in terabits per second, expressed as a decimal integer
Values—
1 to 4

 

Giga-bps
the reference bandwidth in gigabits per second, expressed as a decimal integer
Values—
1 to 999

 

Mega-bps
the reference bandwidth in megabits per second, expressed as a decimal integer
Values—
1 to 999

 

Kilo-bps
the reference bandwidth in kilobits per second, expressed as a decimal integer
Values—
1 to 999

 

rsvp-shortcut

Syntax 
rsvp-shortcut
no rsvp-shortcut
Context 
config>router>isis
Description 

This command enables the use of an RSVP-TE shortcut for resolving IS-IS routes. When the command is enabled, IS-IS includes RSVP-TE LSPs originating on this node and terminating on the router ID of a remote node as direct links with a metric equal to the operational metric provided by MPLS.

The SPF algorithm will always use the IGP metric to build the SPF tree, and the LSP metric value does not update the SPF tree calculation. During the IP reach to determine the reachability of nodes and prefixes, LSPs are overlaid and the LSP metric is used to determine the subset of paths that are of an equal lowest cost to reach a node or a prefix. If the relative-metric option for this LSP is enabled (in the config>router>mpls>lsp>igp-shortcut context), IS-IS will apply the shortest cost between the endpoints of the LSP plus the value of the offset, instead of the LSP operational metric, when calculating the cost of a prefix that is resolved to the LSP.

When a prefix is resolved to a tunnel next hop, the packet is sent labeled with the label stack corresponding to the NHLFE of the RSVP-TE LSP. Any network event that causes an RSVP-TE LSP to go down will trigger a full SPF calculation, which may result in a new route being installed over another RSVP-TE LSP shortcut as a tunnel next hop or over a regular IP next hop.

When the rsvp-shortcut command is enabled, all RSVP-TE LSPs originating on this node are eligible by default as long as the destination address of the LSP, as configured with the config>router>mpls> lsp>to command, corresponds to a router ID of a remote node. A specific LSP can be excluded from being used as a shortcut with the config>router>mpls> lsp>no igp-shortcut command.

If ECMP is enabled on the system and multiple equal-cost paths exist for the route over a set of tunnel next hops (based on the hashing routine supported for IPv4 packets), there are two possibilities:

  1. if the destination is the tunnel endpoint, the system selects the tunnel with the lowest tunnel ID (the IP next hop is never used)
  2. if the destination is different from the tunnel endpoint, the system:
    1. selects tunnel endpoints where the LSP metric is lower than the IGP cost
    2. prefers tunnel endpoints over IP next hops

ECMP is not performed across both the IP and tunnel next hops.

IS-IS can populate the multicast RTM with the prefix IP next hop when both rsvp-shortcut and multicast-import are enabled. The unicast RTM can still use the tunnel next hop for the same prefix.

The forwarding adjacency feature (advertise-tunnel-link) can be enabled independently from the shortcuts feature. If both features are enabled for a given IS-IS instance, the forwarding adjacency feature takes precedence.

The no form of this command disables the resolution of IGP routes using RSVP shortcuts.

Default 

no rsvp-shortcut

segment-routing

Syntax 
[no] segment-routing
Context 
config>router>isis
Description 

This command enables the context to configure segment routing parameters within an IGP instance.

Segment routing adds to IS-IS and OSPF routing protocols the ability to perform shortest path routing and source routing using the concept of abstract segment. An abstract segment can represent a local prefix of a node, a specific adjacency of the node (interface or next-hop), a service context, or a specific explicit path over the network. For each segment, the IGP advertises an identifier referred to as the segment ID (SID).

When segment routing is used together with the MPLS data plane, the SID is a standard MPLS label. A router forwarding a packet using segment routing will push one or more MPLS labels.

Segment routing using MPLS labels can be used in both shortest path routing applications and traffic engineering applications. On the 7705 SAR, segment routing implements the shortest path forwarding application.

After segment routing is successfully enabled in the IS-IS or OSPF instance, the router will perform the following operations:

  1. advertise the Segment Routing Capability sub-TLV to routers in all areas or levels of this IGP instance. However, only neighbors with which the IGP instance established an adjacency will interpret the SID and label range information and use it for calculating the label to swap to or push for a particular resolved prefix SID.
  2. advertise the assigned index for each configured node SID in the new prefix SID sub-TLV with the N-flag (node SID flag) set. The segment routing module then programs the incoming label map (ILM) with a pop operation for each local node SID in the data path.
  3. automatically assign and advertise an adjacency SID label for each formed adjacency over a network IP interface in the new Adjacency SID sub-TLV. The segment routing module programs the incoming label map (ILM) with a pop operation, in effect with a swap to an implicit null label operation, for each advertised adjacency SID.
  4. resolve received prefixes, and if a prefix SID sub-TLV exists, the segment routing module programs the ILM with a swap operation and programs an LSP ID to NHLFE (LTN) with a push operation, both pointing to the primary/LFA NHLFE. An SR tunnel is also added to the TTM.

When the user enables segment routing in an IGP instance, the main SPF and LFA SPF are computed normally and the primary next hop and LFA backup next hop for a received prefix are added to the RTM without the label information advertised in the prefix SID sub-TLV.

adj-sid-hold

Syntax 
adj-sid-hold seconds
no adj-sid-hold
Context 
config>router>isis>segment-routing
Description 

This command configures a timer to hold the ILM or LTN of an adjacency SID following a failure of the adjacency.

When an adjacency to a neighbor fails, the IGP will withdraw the advertisement of the link TLV information as well as its adjacency SID sub-TLV. However, the ILM or LTN record of the adjacency SID must be kept in the data path to maintain forwarding using the LFA or remote LFA backup for a sufficient length of time to allow the ingress LER and other routers that use this adjacency SID to activate a new path after the IGP converges.

If the adjacency is restored before the timer expires, the timer is aborted as soon as the new ILM or LTN records are updated with the new primary and backup NHLFE information.

The no form of the command removes the adjacency SID hold time.

Default 

15

Parameters 
seconds—
the adjacency SID hold time, in seconds
Values—
1 to 300

 

entropy-label

Syntax 
entropy-label {force-disable | enable}
no entropy-label
Context 
config>router>isis>segment-routing
Description 

This command, when used with the force-disable keyword, instructs the system to ignore any received IGP advertisements of entropy label capability relating to remote nodes in the network. The command also prevents a user from configuring override-tunnel-elc for the IGP instance.

The no version of this command enables the processing of any received IGP advertisements of entropy label capability. Using the enable keyword has the same effect.

Default 

entropy-label enable

Parameters 
force-disable —
forces the system to ignore any received advertisements of entropy label capability signaled in the IGP
enable —
enables the system to process any received advertisements of entropy label capability signaled in the IGP

export-tunnel-table

Syntax 
export-tunnel-table ldp
no export-tunnel-table
Context 
config>router>isis>segment-routing
Description 

This command enables the exporting of LDP tunnels from the TTM to an IGP instance for the purpose of stitching an SR tunnel to an LDP FEC for the same destination IPv4 /32 prefix.

When this command is enabled, the IGP monitors the LDP tunnel entries in the TTM. Whenever an LDP tunnel destination matches a prefix for which IGP received a prefix SID sub-TLV from the mapping server, the IGP instructs the SR module to program the SR ILM and to stitch it to the LDP tunnel endpoint.

The no form of this command disables the exporting of LDP tunnels to the IGP instance.

Default 

no export-tunnel-table

Parameters 
ldp—
exports LDP tunnels from the TTM to an IGP instance

mapping-server

Syntax 
[no] mapping-server
Context 
config>router>isis>segment-routing
Description 

This command enables the context to enable the SR mapping server feature for an IS-IS instance.

The mapping server feature allows the configuration and advertisement via IS-IS of the node SID index for IS-IS prefixes of routers that are in the LDP domain. The router that is acting as a mapping server uses a prefix SID sub-TLV within the SID/Label Binding TLV in IS-IS to advertise a node SID index.

The no form of this command deletes the mapping server.

sid-map

Syntax 
sid-map node-sid {index value [range value]} prefix {ip-address/mask | ip-address netmask} [set-flags {s}] [level {1 | 2 | 1/2}]
no sid-map node-sid index value
Context 
config>router>isis>segment-routing>mapping-server
Description 

This command configures the SR mapping server database for an IS-IS instance.

The node-sid index can be configured for one prefix or a range of prefixes by specifying the index value or a value range.

Only the first prefix in a consecutive range of prefixes must be entered. If the first prefix has a mask lower than 32, the SID/Label Binding TLV is advertised but the router does not resolve the prefix SIDs; a trap is originated instead.

The set-flags s option indicates to the IS-IS network routers that the flooding of the SID/Label Binding TLV applies to the entire domain. A router that receives the TLV advertisement leaks it between IS-IS levels 1 and 2. If leaked from level 2 to level 1, the D-flag must be set; this prevents the TLV from being leaked back into level 2. The S-flag is not defined by default; if it is not configured, the TLV is not leaked by routers receiving the mapping server advertisement.

The level option specifies the mapping server’s flooding scope for the generated SID/Label Binding TLV using t. The default flooding scope of the mapping server is level 1/2.

The no form of this command deletes the range of node SIDs beginning with the specified index value.

Parameters 
index value
specifies the node SID index for the IS-IS prefix that will be advertised in a SID/Label Binding TLV
Values—
0 to 4294967295

 

range value
specifies the node SID range for the IS-IS prefixes that will be advertised in a SID/Label Binding TLV
Values—
0 to 65535

 

ip-address—
specifies the IP address
Values—
a.b.c.d. (host bits must be 0)

 

mask—
specifies the subnet mask
Values—
0 to 32

 

netmask—
specifies the subnet mask in dotted-decimal notation
Values—
0.0.0.0 to 255.255.255.255

 

set-flags s—
specifies that the flooding of the SID/Label Binding TLV applies to the entire domain
level {1 | 2 | 1/2}
specifies the mapping server flooding scope for the generated SID/Label Binding TLV
Default—
1/2

prefix-sid-range

Syntax 
prefix-sid-range global
prefix-sid-range start-label label-value max-index index-value
no prefix-sid-range
Context 
config>router>isis>segment-routing
Description 

This command configures the prefix SID index range and offset label value for an IGP instance.

The key parameter is the configuration of the prefix SID index range and the offset label value that this IGP instance will use. Because each prefix SID represents a network global IP address, the SID index for a prefix must be unique network-wide. Therefore, all routers in the network are expected to configure and advertise the same prefix SID index range for an IGP instance. However, the label value used by each router to represent this prefix, that is, the label programmed in the ILM, can be local to that router by the use of an offset label, referred to as a start label:

Local Label (Prefix SID) = start-label + {SID index}

The label operation in the network is very similar to LDP when operating in the independent label distribution mode (RFC 5036, LDP Specification), with the difference that the label value used to forward a packet to each downstream router is computed by the upstream router based on the advertised prefix SID index using the above formula.

There are two mutually exclusive modes of operation for the prefix SID range on the router: global mode and per-instance mode.

In global mode, the user configures the global value and the IGP instance assumes that the start label value is the lowest label value in the Segment Routing Global Block (SRGB) and the prefix SID index range size is equal to the range size of the SRGB. When one IGP instance selects the global option for the prefix SID range, all IGP instances on the system must do the same. The user must shut down the segment routing context and disable the prefix-sid-range command in all IGP instances in order to change the SRGB. When the SRGB is changed, the user must re-enable the prefix-sid-range command. The SRGB range change will fail if an already allocated SID index/label goes out of range.

In per-instance mode, the user partitions the SRGB into non-overlapping sub-ranges among the IGP instances. The user configures a subset of the SRGB by specifying the start label value and the prefix SID index range size. All resulting net label values (start-label + index) must be within the SRGB or the configuration will fail. The 7705 SAR checks for overlaps of the resulting net label value range across IGP instances and will strictly enforce no overlapping of these ranges. The user must shut down the segment routing context of an IGP instance in order to change the SID index/label range of that IGP instance using the prefix-sid-range command. A range change will fail if an already allocated SID index/label goes out of range. The user can change the SRGB without shutting down the segment routing context as long as it does not reduce the current per-IGP instance SID index/label range defined with the prefix-sid-range command. Otherwise, the user must shut down the segment routing context of the IGP instance, and disable and re-enable the prefix-sid-range command.

Default 

no prefix-sid-range

Parameters 
label-value—
specifies the label offset for the SR label range of this IGP instance
Values—
0 to 524287

 

index-value—
specifies the maximum value of the prefix SID index range for this IGP instance
Values—
1 to 524287

 

tunnel-mtu

Syntax 
tunnel-mtu bytes
no tunnel-mtu
Context 
config>router>isis>segment-routing
Description 

This command configures the MTU of all SR tunnels within each IGP instance.

The MTU of an SR tunnel populated into the TTM is determined in the same way as the MTU of an IGP tunnel (for example, an LDP LSP) based on the outgoing interface MTU minus the label stack size. Remote LFA can add, at most, one more label to the tunnel for a total of two labels. There is no default value for this command. If the user does not configure an SR tunnel MTU, the MTU, in bytes, is determined by IGP as follows:

SR_Tunnel_MTU = MIN {Cfg_SR_MTU, IGP_Tunnel_MTU – (1 + frr-overhead)× 4}

where:

  1. Cfg_SR_MTU is the MTU configured by the user for all SR tunnels within an IGP instance using the tunnel-mtu command. If no value is configured by the user, the SR tunnel MTU is determined by the IGP interface calculation explained in the following bullet point
  2. IGP_Tunnel_MTU is the minimum of the IS-IS or OSPF interface MTU among all the ECMP paths or among the primary and LFA backup paths of this SR tunnel
  3. frr-overhead is set to 1 if the segment-routing and remote-lfa options are enabled in the IGMP instance. Otherwise, it is set to 0.

The SR tunnel MTU is dynamically updated whenever any of the above parameters used in its calculation changes. This includes if the set of the tunnel next hops changes or the user changes the configured SR MTU or interface MTU value.

Default 

no tunnel-mtu

Parameters 
bytes—
specifies the size of the MTU in bytes
Values—
512 to 9198

 

tunnel-table-pref

Syntax 
tunnel-table-pref preference
no tunnel-table-pref
Context 
config>router>isis>segment-routing
Description 

This command configures the TTM preference of shortest path SR tunnels created by the IGP instance. This is used for BGP shortcuts, VPRN auto-bind, or BGP transport tunnel when the tunnel binding commands are configured to the any value, which parses the TTM for tunnels in the protocol preference order. The user can choose either the global TTM preference or explicitly list the tunnel types they want to use. If the user lists the tunnel types explicitly, the TTM preference is still used to select one type over the other. In both cases, a fallback to the next preferred tunnel type is performed if the selected type fails. A reversion to a more preferred tunnel type is performed as soon as one is available.

The segment routing module adds to the TTM an SR tunnel entry for each resolved remote node SID prefix and programs the data path having the corresponding LTN with the push operation pointing to the primary and LFA backup NHLFEs.

The default preference for shortest path SR tunnels in the TTM is set lower than LDP tunnels but higher than BGP tunnels to allow controlled migration of customers without disrupting their current deployment when they enable segment routing. The following list shows the value of the default preference for the various tunnel types. This includes the preference of SR tunnels based on shortest path (referred to as SR-ISIS and SR-OSPF).

Note:

The preference of the SR-TE LSP is not configurable and is the second most preferred tunnel type after RSVP-TE. The preference is the same whether the SR-TE LSP was resolved in IS-IS or OSPF.

The global default TTM preference for the tunnel types is as follows:

  1. ROUTE_PREF_RSVP              7
  2. ROUTE_PREF_SR_TE            8
  3. ROUTE_PREF_LDP                 9
  4. ROUTE_PREF_OSPF_TTM   10
  5. ROUTE_PREF_ISIS_TTM      11
  6. ROUTE_PREF_BGP_TTM     12
  7. ROUTE_PREF_GRE             255

The default value for SR-ISIS or SR-OSPF is the same regardless of whether one or more IS-IS or OSPF instances programmed a tunnel for the same prefix. The selection of an SR tunnel in this case is based on the lowest IGP instance ID.

Default 

11

Parameters 
preference—
specifies the integer value to represent the preference of IS-IS SR tunnels in the TTM
Values—
1 to 255

 

strict-adjacency-check

Syntax 
[no] strict-adjacency-check
Context 
config>router>isis
Description 

This command enables strict checking of address families (IPv4 and IPv6) for IS-IS adjacencies. When enabled, adjacencies will not come up unless both routers have exactly the same address families configured. If there is an existing adjacency with unmatched address families, it will be torn down. By ensuring that adjacencies are only established if both routers have the same address families, this command prevents the blackholing of traffic that may occur when IPv4 and IPv6 topologies are different.

When the command is disabled, both routers only need to have one common address family to establish the adjacency. A BFD session failure for either IPv4 or IPv6 will cause the routes for the other address family to be removed as well.

Default 

no strict-adjacency-check

summary-address

Syntax 
summary-address {ip-prefix/prefix-length | ip-prefix [netmask]} level
no summary-address {ip-prefix/prefix-length | ip-prefix [netmask]}
Context 
config>router>isis
Description 

This command creates summary addresses.

Default 

no summary-address

Parameters 
ip-prefix/prefix-length—
IP prefix and mask length
Values—
ipv4-prefix               a.b.c.d (host bits must be 0)
ipv4-prefix-length    0 to 32
ipv6-prefix               x:x:x:x:x:x:x:x   (eight 16-bit pieces)
                                 x:x:x:x:x:x:d.d.d.d
                                 x: [0..FFFF]H
                               d: [0..255]D
ipv6-prefix-length    0 to 128

 

netmask—
the subnet mask in dotted-decimal notation
Values—
a.b.c.d (0.0.0.0 to 255.255.255.255) (network bits all 1 and host bits all 0)

 

level—
the IS-IS level
Values—
level-1, level-2, level-1/2

 

suppress-attached-bit

Syntax 
[no] suppress-attached-bit
Context 
config>router>isis
Description 

This command suppresses the setting of the attached (ATT) bit in level 1 LSPs originated by this level 1/2 router to prevent all level 1 routers in the area from installing a default route to this router.

The no form of the command enables the setting of the ATT bit.

Default 

no suppress-attached-bit

timers

Syntax 
[no] timers
Context 
config>router>isis
Description 

This command configures the IS-IS timer values.

lsp-wait

Syntax 
lsp-wait lsp-wait [lsp-initial-wait initial-wait] [lsp-second-wait second-wait]
no lsp-wait
Context 
config>router>isis>timers
Description 

This command is used to customize LSP generation throttling. Timers that determine when to generate the first, second, and subsequent LSPs can be controlled with this command. Subsequent LSPs are generated at increasing intervals of the second lsp-wait timer until a maximum value is reached.

Note:

The IS-IS timer granularity is 100 ms. Timer values are rounded down to the nearest supported value; for example, a configured value of 550 ms is internally rounded down to 500 ms.

Default 

lsp-wait 5000

Parameters 
lsp-wait —
the maximum interval, in milliseconds, between two consecutive occurrences of an LSP being generated
Values—
10 to 120000

 

Default—
5000
initial-wait —
the initial LSP generation delay, in milliseconds. Values less than 100 ms are internally rounded down to 0, so that there is no added initial LSP generation delay.
Values—
10 to 100000

 

Default—
10
second-wait —
the hold time, in milliseconds, between the first and second LSP generation
Values—
10 to 100000

 

Default—
1000

spf-wait

Syntax 
spf-wait spf-wait [spf-initial-wait initial-wait] [spf-second-wait second-wait]
no spf-wait
Context 
config>router>isis>timers
Description 

This command defines the maximum interval, in milliseconds, between two consecutive SPF calculations. Timers that determine when to initiate the first, second, and subsequent SPF calculations after a topology change occurs can be controlled with this command.

Subsequent SPF runs (if required) will occur at exponentially increasing intervals of the spf-second-wait interval. For example, if the spf-second-wait interval is 1000, the next SPF will run after 2000 ms, the SPF after that will run after 4000 ms, and so on, until it reaches the spf-wait value. The SPF interval will stay at the spf-wait value until there are no more SPF runs scheduled in that interval. After a full interval without any SPF runs, the SPF interval will drop back to the spf-initial-wait value.

Note:

The IS-IS timer granularity is 100 ms. Timer values are rounded down to the nearest supported value; for example, a configured value of 550 ms is internally rounded down to 500 ms.

Default 

spf-wait 10000

Parameters 
spf-wait —
the maximum interval, in milliseconds, between two consecutive SPF calculations
Values—
10 to 120000

 

Default—
10000
initial-wait —
the initial SPF calculation delay, in milliseconds, after a topology change
Values—
10 to 100000

 

Default—
1000
second-wait —
the hold time, in milliseconds, between the first and second SPF calculation
Values—
10 to 100000

 

Default—
1000

traffic-engineering

Syntax 
[no] traffic-engineering
Context 
config>router>isis
Description 

This command enables traffic engineering and determines if IGP shortcuts are required.

The no form of the command disables traffic-engineered route calculations.

Default 

no traffic-engineering

unicast-import-disable

Syntax 
[no] unicast-import-disable [ipv4]
Context 
config>router>isis
Description 

This command allows one IGP to import its routes into the multicast RTM (also known as the RPF RTM [Reverse Path Forwarding - Route Table Manager]) while another IGP imports routes only into the unicast RTM. Import policies can redistribute routes from an IGP protocol into the RPF RTM. By default, the IGP routes will not be imported into the RPF RTM, since such an import policy must be explicitly configured.

The no form of the command enables importing IGP routes into the RPF RTM.

Default 

no unicast-import-disable ipv4

5.11.2.1.3. Interface Commands

interface

Syntax 
[no] interface ip-int-name
Context 
config>router>isis
Description 

This command enables the context to configure an IS-IS interface.

When an area is defined, the interfaces belong to that area. Interfaces cannot belong to other areas.

If the interface is a POS channel, the OSI Network Layer Control Protocol (OSINLCP) is enabled when the interface is created and removed when the interface is deleted.

The no form of the command deletes the IS-IS interface configuration for this interface. The shutdown command in the config>router>isis>interface context can be used to disable an interface without removing the configuration for the interface.

Default 

no interface

Parameters 
ip-int-name—
the IP interface name. Interface names must be unique within the group of defined IP interfaces for the config>router>interface command. An interface name cannot be in the form of an IP address. Interface names can be any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.

bfd-enable

Syntax 
[no] bfd-enable ipv4
Context 
config>router>isis>interface
Description 

This command enables the use of bidirectional forwarding (BFD) to control IPv4 adjacencies. By enabling BFD on a given IS-IS interface, the state of the interface is tied to the state of the BFD session between the local node and the remote node. The parameters used for BFD are set via the BFD command under the IP interface.

The no form of this command removes BFD from the associated IPv4 adjacency.

Default 

no bfd-enable ipv4

csnp-interval

Syntax 
csnp-interval seconds
no csnp-interval
Context 
config>router>isis>interface
Description 

This command configures the interval, in seconds, to send complete sequence number PDUs (CSNPs) from the interface. IS-IS must send CSNPs periodically.

The no form of the command reverts to the default value.

Default 

csnp-interval 10 – CSN PDUs are sent every 10 s for LAN interfaces

csnp-interval 5 – CSN PDUs are sent every 5 s for point-to-point interfaces

Parameters 
seconds—
the CSNP interval expressed in seconds
Values—
1 to 65535

 

hello-auth-keychain

Syntax 
hello-auth-keychain name
no hello-auth-keychain
Context 
config>router>isis>interface
config>router>isis>interface>level
Description 

This command associates a Hello authentication keychain with the IS-IS interface or interface level. The keychain is a collection of keys used to authenticate IS-IS messages from remote peers. The keychain allows the rollover of authentication keys during the lifetime of a session and also supports stronger authentication algorithms than clear text and MD5.

The keychain must already be defined in the config>system>security>keychain context.

Either the hello-authentication-key command or the hello-auth-keychain command can be used by IS-IS, but both cannot be supported at the same time. If both commands are configured, the hello-auth-keychain configuration will be applied and the hello-authentication-key command will be ignored.

Default 

no hello-auth-keychain

Parameters 
name—
the name of the keychain, up to 32 characters

hello-authentication-key

Syntax 
hello-authentication-key {authentication-key | hash-key} [hash | hash2]
no hello-authentication-key
Context 
config>router>isis>interface
config>router>isis>interface>level
Description 

This command configures the authentication key (password) for Hello PDUs. Neighboring routers use the password to verify the authenticity of Hello PDUs sent from this interface. Both the Hello authentication key and the Hello authentication type on a segment must match. The hello-authentication-type command must also be entered.

To configure the Hello authentication key for all levels configured for the interface, use the hello-authentication-key command in the config>router>isis>interface context.

To configure or override the Hello authentication key for a specific level, use the hello-authentication-key command in the config>router>isis>interface>level context.

If both IS-IS authentication and Hello authentication are configured, Hello messages are validated using Hello authentication. If only IS-IS authentication is configured, it will be used to authenticate all IS-IS protocol PDUs, including Hello PDUs.

Either the hello-authentication-key command or the hello-auth-keychain command can be used by IS-IS, but both cannot be supported at the same time. If both commands are configured, the hello-auth-keychain configuration will be applied and the hello-authentication-key command will be ignored.

The no form of the command removes the hello authentication key from the configuration.

Default 

no hello-authentication-key

Parameters 
authentication-key—
the authentication key can be any combination of ASCII characters up to 254 characters in length (unencrypted). If spaces are used in the string, the entire string must be enclosed within double quotes (“ ”).
hash-key—
the hash key can be any combination of ASCII characters up to 352 characters in length (encrypted) or 451 characters in length (if the hash2 parameter is used). If spaces are used in the string, the entire string must be enclosed within double quotes (“ ”).

This is useful when a user must configure the parameter, but for security purposes, the actual unencrypted key value is not provided.

hash—
specifies that the key is entered in an encrypted form. If the hash parameter is not used, the key is assumed to be in a non-encrypted, clear text form. For security, all keys are stored in encrypted form in the configuration file with the hash parameter specified.
hash2—
specifies that the key is entered in a more complex encrypted form. If the hash2 parameter is not used, the less encrypted hash form is assumed.

hello-authentication-type

Syntax 
hello-authentication-type {password | message-digest}
no hello-authentication-type
Context 
config>router>isis>interface
config>router>isis>interface>level
Description 

This command enables Hello authentication at either the interface or level context. Both the hello authentication key and the hello authentication type on a segment must match. The hello-auth-keychain command must also be entered.

To configure the hello authentication type for all levels configured for the interface, use the hello-authentication-type command in the config>router>isis>interface context.

To configure or override the hello authentication type for a specific level, use the hello-authentication-type command in the config>router>isis>interface>level context.

The no form of the command disables Hello PDU authentication.

Default 

no hello-authentication-type

Parameters 
password—
enables simple password (plain text) authentication. If authentication is enabled and no authentication type is specified in the command, simple password authentication is enabled.
message-digest—
enables message-digest MD5 authentication in accordance with RFC 1321. If this option is configured, at least one message-digest-key must be configured.

hello-interval

Syntax 
hello-interval seconds
no hello-interval
Context 
config>router>isis>interface>level
Description 

This command configures the interval between IS-IS Hello PDUs issued on the interface at this level. The hello-interval, along with the hello-multiplier, is used to calculate a hold time, which is communicated to a neighbor in a Hello PDU.

Note:

The neighbor hold time is (hello multiplier × hello interval) on non-designated intermediate system broadcast interfaces and point-to-point interfaces and is (hello multiplier × hello interval / 3) on designated intermediate system broadcast interfaces. Hello values can be adjusted for faster convergence, but the hold time should always be > 3 to reduce routing instability.

The no form of this command reverts to the default value.

Default 

3 – for designated intermediate system interfaces

9 – for non-designated intermediate system interfaces and point-to-point interfaces

Parameters 
seconds—
the hello interval, in seconds, expressed as a decimal integer
Values—
1 to 20000

 

hello-multiplier

Syntax 
hello-multiplier multiplier
no hello-multiplier
Context 
config>router>isis>interface>level
Description 

This command configures a hello multiplier. The hello-multiplier, along with the hello-interval, is used to calculate a hold time, which is communicated to a neighbor in a Hello PDU.

The hold time is the time in which the neighbor expects to receive the next Hello PDU. If the neighbor receives a Hello within this time, the hold time is reset. If the neighbor does not receive a Hello within the hold time, it brings the adjacency down.

Note:

The neighbor hold time is (hello multiplier × hello interval) on non-designated intermediate system broadcast interfaces and point-to-point interfaces and is (hello multiplier × hello interval / 3) on designated intermediate system broadcast interfaces. Hello values can be adjusted for faster convergence, but the hold time should always be > 3 to reduce routing instability.

The no form of this command reverts to the default value.

Default 

3

Parameters 
multiplier—
the multiplier for the hello interval, in seconds, expressed as a decimal integer
Values—
2 to 100

 

interface-type

Syntax 
interface-type {broadcast | point-to-point}
no interface-type
Context 
config>router>isis>interface
Description 

This command configures the interface type to be either broadcast or point-to-point.

Use this command to set the interface type of an Ethernet link to point-to-point to avoid having to carry the broadcast adjacency maintenance overhead of the Ethernet link, provided the link is used as a point-to-point link.

If the interface type is not known when the interface is added to IS-IS, and the IP interface is subsequently bound (or moved) to a different interface type, this command must be entered manually.

The no form of the command reverts to the default value.

Default 

broadcast – if the physical interface is Ethernet or unknown

point-to-point – if the physical interface is T1, E1, or SONET/SDH

Parameters 
broadcast—
configures the interface to maintain this link as a broadcast network. To significantly improve adjacency forming and network convergence, a network should be configured as point-to-point if only two routers are connected, even if the network is a broadcast media such as Ethernet.
point-to-point—
configures the interface to maintain this link as a point-to-point link

ipv4-node-sid

Syntax 
ipv4-node-sid index index-value
ipv4-node-sid label label-value
no ipv4-node-sid
Context 
config>router>isis>interface
Description 

This command assigns a node SID index or label value to the prefix representing the primary address of an IPv4 network interface of type loopback. Only a single node SID can be assigned to an interface. The secondary address of an IPv4 interface cannot be assigned a node SID index and does not inherit the SID of the primary IPv4 address.

This command fails if the network interface is not of type loopback or if the interface is defined in an IES or a VPRN context.

Assigning the same SID index or label value to the same interface in two different IGP instances is not allowed within the same node.

The value of the label or index SID is taken from the range configured for this IGP instance. When using the global mode of operation, the segment routing module checks that the same index or label value is not assigned to more than one loopback interface address. When using the per-instance mode of operation, this check is not required because the index, and therefore the label ranges, of IGP instances are not allowed to overlap.

Default 

no ipv4-node-sid

Parameters 
index-value—
specifies the index value
Values—
0 to 4294967295

 

label-value—
specifies the label value
Values—
0 to 4294967295

 

ipv6-node-sid

Syntax 
ipv6-node-sid index index-value
ipv6-node-sid label label-value
no ipv6-node-sid
Context 
config>router>isis>interface
Description 

This command assigns a node SID index or label value to the prefix representing the primary address of an IPv6 network interface of type loopback. Only a single node SID can be assigned to an IPv6 interface. When an IPv6 interface has multiple global addresses, the primary address is always the first one in the list, as displayed by the interface info command.

This command fails if the network interface is not of type loopback or if the interface is defined in an IES or a VPRN context.

Assigning the same SID index or label value to the same interface in two different IGP instances is not allowed within the same node.

The value of the label or index SID is taken from the range configured for this IGP instance. When using the global mode of operation, the segment routing module checks that the same index or label value is not assigned to more than one loopback interface address. When using the per-instance mode of operation, this check is not required because the index, and therefore the label ranges, of IGP instances are not allowed to overlap.

Default 

no ipv6-node-sid

Parameters 
index-value—
specifies the index value
Values—
0 to 4294967295

 

label-value—
specifies the label value
Values—
0 to 4294967295

 

lfa-policy-map

Syntax 
lfa-policy-map route-nh-template template-name
no lfa-policy-map
Context 
config>router>isis>interface
Description 

This command applies a route next-hop policy template to an IS-IS interface. When a route next-hop policy template is applied to an interface in IS-IS, it is applied in both level 1 and level 2.

If the interface has been excluded from LFA with the loopfree-alternate-exclude command, the LFA policy has no effect on the interface.

If the route next-hop policy template is applied to a loopback interface or to the system interface, the command will not be rejected, but the policy will have no effect on the interface.

The no form of the command deletes the mapping of a route next-hop policy template to an IS-IS interface.

Default 

no lfa-policy-map

Parameters 
template-name—
the name of an existing template

lsp-pacing-interval

Syntax 
lsp-pacing-interval milliseconds
no lsp-pacing-interval
Context 
config>router>isis>interface
Description 

This command configures the interval between link-state PDUs (LSPs) sent from this interface. Controlling the time between LSPs ensures that adjacent neighbors are not being bombarded with excessive data.

A value of 0 means that no LSPs are sent from the interface.

The no form of the command reverts to the default value.

Default 

100

Parameters 
milliseconds—
the interval that LSPs can be sent from the interface, expressed as a decimal integer
Values—
0 to 65335

 

mesh-group

Syntax 
mesh-group [value | blocked]
no mesh-group
Context 
config>router>isis>interface
Description 

This command assigns an interface to a mesh group. Mesh groups limit the amount of flooding that occurs when a new or changed LSP is advertised throughout an area.

All routers in a mesh group should be fully meshed. When LSPs need to be flooded, only a single copy is received rather than one copy per neighbor.

To create a mesh group, configure the same mesh group value for each interface that is part of the mesh group. All routers must have the same mesh group value configured for all interfaces that are part of the mesh group.

To prevent an interface from flooding LSPs, the optional blocked parameter can be specified.

Caution:

Configure mesh groups carefully. It is easy to create isolated islands that will not receive updates if other links fail.

The no form of the command removes the interface from the mesh group.

Default 

no mesh-group

Parameters 
value—
the unique decimal integer that distinguishes this mesh group from other mesh groups on this router or on other routers
Values—
1 to 2000000000

 

blocked—
prevents an interface from flooding LSPs

metric

Syntax 
metric metric
no metric
Context 
config>router>isis>interface>level
Description 

This command configures the metric used for the level on this IS-IS interface.

To calculate the lowest cost to reach a given destination, each configured level on each interface must have a cost. The costs for each level on an interface may be different.

If the metric is not configured, the default value of 10 is used unless the reference-bandwidth is configured.

The no form of the command reverts to the default value.

Default 

no metric (10)

Parameters 
metric—
the metric assigned to this level on this interface, expressed as a decimal integer
Values—
1 to 16777215

 

passive

Syntax 
[no] passive
Context 
config>router>isis>interface
config>router>isis>interface>level
Description 

This command adds the passive attribute to the IS-IS interface, which causes the interface to be advertised as an IS-IS interface without running the IS-IS protocol. Normally, only interface addresses that are configured for IS-IS are advertised as IS-IS interfaces at the level that they are configured.

If the passive mode is enabled, the interface or the interface at the specified level ignores ingress IS-IS protocol PDUs and will not transmit IS-IS protocol PDUs.

The no form of the command removes the passive attribute.

Default 

no passive

priority

Syntax 
priority number
no priority
Context 
config>router>isis>interface>level
Description 

This command configures the priority of the IS-IS interface that is used in an election of the designated router (DIS) on a multi-access network.

This parameter is only used if the interface is a broadcast type.

The priority is included in Hello PDUs transmitted by the interface on a multi-access network. The router with the highest priority becomes the designated router. The designated router is responsible for sending LSPs about the network and the routers attached to it.

The no form of the command reverts to the default value.

Default 

64

Parameters 
number—
the priority for this interface at this level, expressed as a decimal integer
Values—
0 to 127

 

retransmit-interval

Syntax 
retransmit-interval seconds
no retransmit-interval
Context 
config>router>isis>interface
Description 

This command specifies the interval, in seconds, that IS-IS will wait before retransmitting an unacknowledged LSP to an IS-IS neighbor.

If the retransmit interval expires and no acknowledgment has been received, the LSP will be retransmitted.

The no form of this command reverts to the default interval.

Default 

5

Parameters 
seconds—
the retransmit interval, in seconds, expressed as a decimal integer
Values—
1 to 65335

 

sid-protection

Syntax 
[no] sid-protection
Context 
config>router>isis>interface
Description 

This command enables or disables adjacency SID protection by LFA and remote LFA.

LFA and remote LFA Fast Reroute (FRR) protection is enabled for all node SIDs and local adjacency SIDs when the user enables the loopfree-alternate option in IS-IS or OSPF at the LER and LSR. However, there may be applications where the user never wants traffic to divert from the strict hop computed by CSPF for an SR-TE LSP. In this case, the user can disable protection for all adjacency SIDs formed over a particular network IP interface using this command.

The protection state of an adjacency SID is advertised in the B flag of the IS-IS or OSPF Adjacency SID sub-TLV.

Default 

sid-protection

5.11.2.2. Show Commands

Note:

The following command outputs are examples only; actual displays may differ depending on supported functionality and user configuration.

isis

Syntax 
isis all
isis [isis-instance]
Context 
show>router
Description 

This command enables the context to display IS-IS information.

Parameters 
all—
enables the context to display all IS-IS instances
isis-instance—
enables the context to display the specified IS-IS instance ID. If no isis-instance is specified, instance 0 is used.
Values—
0 to 31

 

adjacency

Syntax 
adjacency [ip-int-name | ip-address | nbr-system-id] [detail]
Context 
show>router>isis
Description 

This command displays information about IS-IS neighbors. If no parameters are specified, adjacencies for the specified IS-IS instance are displayed. If detail is specified, operational and statistical information is displayed.

To display adjacency information for all IS-IS instances, use the show router isis all context.

Parameters 
ip-int-name—
displays only adjacencies with the specified interface
ip-address—
displays only adjacencies with the specified IP address
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

nbr-system-id—
displays only the adjacency with the specified system ID
Values—
6-octet system identifier (xxxx.xxxx.xxxx)

 

detail—
displays detailed information about the adjacency
Output 

The following output is an example of IS-IS adjacency information, and Table 65 describes the fields for both summary and detailed outputs.

Output Example
A:ALU-A# show router isis adjacency
===============================================================================
Rtr Base ISIS Instance 0 Adjacency
===============================================================================
System ID           Usage  State Hold Interface                MT-ID            
-------------------------------------------------------------------------------
ALU-B                L1    Up    2    ip-to1                   0
ALU-B                L2    Up    2    ip-to2                   0
ALU-F                L1L2  Up    5    ip-303                   0
-------------------------------------------------------------------------------
Adjacencies : 3
===============================================================================
A:ALU-A#
*A:Sar18 Dut-B>show>router# isis all adjacency
===============================================================================
Rtr Base ISIS Instance 0 Adjacency
===============================================================================
System ID            Usage State Hold Interface                MT-ID
-------------------------------------------------------------------------------
ALU-B                L1    Up    2    ip-to1                   0
ALU-B                L2    Up    2    ip-to2                   0
ALU-F                L1L2  Up    5    ip-303                   0
===============================================================================
===============================================================================
Rtr Base ISIS Instance 1 Adjacency
===============================================================================
System ID                Usage State Hold Interface            MT-ID
-------------------------------------------------------------------------------
No Matching Entries
===============================================================================
===============================================================================
Rtr Base ISIS Instance 2 Adjacency
===============================================================================
System ID                Usage State Hold Interface            MT-ID
-------------------------------------------------------------------------------
No Matching Entries
===============================================================================
Table 65:  Adjacency Field Descriptions 

Label

Description

System ID

System ID of the neighbor

Usage/L. Circ Typ

Level on the interface: L1, L2, or L1/2

State

State of the adjacency: up, down, new, one-way, initializing, or rejected

Hold/Hold Time

Hold time remaining for the adjacency

Interface

Interface name associated with the neighbor

MT-ID

Not applicable. The value 0 is always displayed.

capabilities

Syntax 
capabilities [system-id | lsp-id] [level level ]
Context 
show>router>isis
Description 

This command displays information about the capabilities for the specified IS-IS instance. If no parameters are specified, capabilities for the specified IS-IS instance are displayed. If level is specified, only information about the configured level is displayed.

To display capabilities information for all IS-IS instances, use the show router isis all context.

Parameters 
system-id—
displays only the LSPs related to the specified system ID
lsp-id—
displays only the specified LSP (hostname)
level—
displays information only for the specified level (1 or 2)
Output 

The following output is an example of IS-IS capabilities information, and Table 66 describes the fields.

Output Example
*A:7705:Dut-A# show router isis capabilities 
===============================================================================
Rtr Base ISIS Instance 0 Capabilities
===============================================================================
Displaying Level 1 capabilities
-------------------------------------------------------------------------------
LSP ID    : 7705:Dut-A.00-00                           
  Router Cap : 10.20.1.1, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-A.01-00                           
LSP ID    : 7705:Dut-A.02-00                           
LSP ID    : 7705:Dut-C.00-00                           
  Router Cap : 10.20.1.3, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-C.02-00                           
LSP ID    : 7705:Dut-C.03-00                           
LSP ID    : 7705:Dut-D.00-00                           
  Router Cap : 10.20.1.4, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-B.00-00                           
  Router Cap : 10.20.1.22, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6            
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-B.01-00                           
Level (1) Capability Count : 9
 
 
Displaying Level 2 capabilities
-------------------------------------------------------------------------------
LSP ID    : 7705:Dut-A.00-00                           
  Router Cap : 10.20.1.1, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-A.01-00                           
LSP ID    : 7705:Dut-A.02-00                           
LSP ID    : 7705:Dut-C.00-00                           
  Router Cap : 10.20.1.3, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-C.02-00                           
LSP ID    : 7705:Dut-C.03-00                           
LSP ID    : 7705:Dut-D.00-00                           
  Router Cap : 10.20.1.4, D:0, S:0
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-B.00-00                           
  Router Cap : 10.20.1.22, D:0, S:0   
    TE Node Cap : B E M  
    SR Cap: IPv4 MPLS-IPv6 
       SRGB Base:20000, Range:10001
    SR Alg: metric based SPF
LSP ID    : 7705:Dut-B.01-00                           
Level (2) Capability Count : 9
===============================================================================
Table 66:  IS-IS Capabilities Field Descriptions 

Label

Description

LSP ID

The LSP ID of the specified system ID or hostname

Router Cap

The router IP address and capability

TE Node Cap

The TE node capability

SR Cap

The segment routing capability

SRGB Base

The Segment Routing Global Block (SRGB) base index value and range

SR Alg

The type of SR algorithm used for the specified LSP ID

Level (n) Capability Count

The capability count for the specified level

database

Syntax 
database  [system-id | lsp-id] [detail] [level level]
Context 
show>router>isis
Description 

This command displays information about the IS-IS link-state database. If the system ID and LSP ID are not specified, database entries for the specified IS-IS instance are listed.

To display database information for all IS-IS instances, use the show router isis all context.

Parameters 
system-id—
displays only the LSPs related to the specified system ID
lsp-id—
displays only the specified LSP (hostname)
detail—
displays detailed information on the link-state database entries
level—
displays information only for the specified level (1 or 2)
Output 

The following outputs are examples of IS-IS database information:

  1. IS-IS summary database information (Output Example, Table 67)
  2. IS-IS detailed database information (Output Example, Table 68)
Output Example
A:ALU-A# show router isis database
==============================================================================
Rtr Base ISIS Instance 0 Database 
==============================================================================
LSP ID                                  Sequence Checksum Lifetime Attributes
------------------------------------------------------------------------------
 
Displaying Level 1 database
------------------------------------------------------------------------------
ALU-A.00-00                             0x7      0x51b4   1177     L1L2
Level (1) LSP Count : 1
 
Displaying Level 2 database
------------------------------------------------------------------------------
ALU-A.00-00                             0x7      0x51b4   1014     L1L2
Level (2) LSP Count : 1
==============================================================================
A:ALU-A#
Table 67:  Database Summary Field Descriptions 

Label

Description

LSP ID

LSP IDs are auto-assigned by the originating IS-IS node. The LSP ID consists of three sections: the first 6 bytes are the system ID for that node, followed by a single byte value for the pseudonode generated by that router, followed by a fragment byte that starts at 0.

For example, if a router’s system ID is 1800.0000.0029, the first LSP ID is 1800.0000.0029.00-00. If there are too many routes, LSP ID 1800.0000.0029.00-01 is created to contain the excess routes. If the router is the designated router (or designated intermediate system ([DIS]) on a broadcast network, a pseudonode LSP is created. Usually the internal circuit ID is used to determine the ID assigned to the pseudonode. For instance, for circuit 4, an LSP pseudonode with ID 1800.0000.0029.04-00 is created.

Note: The 7705 SAR learns hostnames and uses the hostname in place of the system ID.

Sequence

The sequence number of the LSP that allows other systems to determine if they have received the latest information from the source

Checksum

The checksum of the entire LSP packet

Lifetime

Length of time, in seconds, that the LSP remains valid

Attributes

OV: the overload bit is set

L1: specifies a level 1 router

L2: specifies a level 2 router

L1L2: specifies a level 1/2 router

ATT: the attachment bit is set; when set, the router can act as a level 2 router and can reach other areas

Output Example
*A:ALU-A# show router isis database detail
==============================================================================
Rtr Base ISIS Instance 0 Database (detail)
==============================================================================
 
Displaying Level 1 database
------------------------------------------------------------------------------
LSP ID    : ALU-A.00-00                                 Level     : L1
Sequence  : 0x7                    Checksum  : 0x51b4   Lifetime  : 1079
Version   : 1                      Pkt Type  : 18       Pkt Ver   : 1
Attributes: L1L2                   Max Area  : 3        Alloc Len : 1492
SYS ID    : 0100.1001.0001         SysID Len : 6        Used Len  : 50
 
TLVs :
  Supp Protocols:
    Protocols     : IPv4
  IS-Hostname   : ALU-A
  Router ID   :
    Router ID   : 10.0.0.0
 
Level (1) LSP Count : 1
 
Displaying Level 2 database
------------------------------------------------------------------------------
LSP ID    : ALU-A.00-00                                 Level     : L2
Sequence  : 0x7                    Checksum  : 0x51b4   Lifetime  : 900
Version   : 1                      Pkt Type  : 20       Pkt Ver   : 1
Attributes: L1L2                   Max Area  : 3        Alloc Len : 1492
SYS ID    : 0100.1001.0001         SysID Len : 6        Used Len  : 50
 
 
TLVs :
  Supp Protocols:
    Protocols     : IPv4
  IS-Hostname   : ALU-A
  Router ID   :
    Router ID   : 10.0.0.0
 
Level (2) LSP Count : 1
Table 68:  Database Detailed Field Descriptions  

Label

Description

LSP ID

LSP IDs are auto-assigned by the originating IS-IS node. The LSP ID consists of three sections: the first 6 bytes are the system ID for that node, followed by a single byte value for the pseudonode generated by that router, followed by a fragment byte that starts at 0.

For example, if a router’s system ID is 1800.0000.0029, the first LSP ID is 1800.0000.0029.00-00. If there are too many routes, LSP ID 1800.0000.0029.00-01 is created to contain the excess routes. If the router is the designated router (or designated intermediate system ([DIS]) on a broadcast network, a pseudonode LSP is created. Usually the internal circuit ID is used to determine the ID assigned to the pseudonode. For instance, for circuit 4, an LSP pseudonode with ID 1800.0000.0029.04-00 is created.

The 7705 SAR learns hostnames and uses the hostname in place of the system ID.

Sequence

The sequence number of the LSP that allows other systems to determine if they have received the latest information from the source

Checksum

The checksum of the entire LSP packet

Lifetime

Length of time, in seconds, that the LSP remains valid

Attributes

OV: the overload bit is set

L1: specifies a level 1 router

L2: specifies a level 2 router

L1L2: specifies a level 1/2 router

ATT: the attachment bit is set; when set, the router can act as a level 2 router and can reach other areas

LSP Count

A sum of all the configured level 1 and level 2 LSPs

LSP ID

A unique identifier for each LSP, consisting of the system ID, pseudonode ID, and LSP name

Version

The version protocol ID extension – always set to 1

Pkt Type

The PDU type number

PkT Ver

The version protocol ID extension – always set to 1

Max Area

The maximum number of area addresses supported

Alloc Len

The amount of memory space allocated for the LSP

SYS ID

The system ID

SysID Len

The length of the system ID field (0 or 6)

Used Len

The actual length of the PDU

Area Address

The area addresses to which the router is connected

Supp Protocols

The supported data protocols

IS-Hostname

The name of the router from which the LSP originated

Virtual Flag

0: level 1 routers report this octet as 0 to all neighbors

1: indicates that the path to a neighbor is a level 2 virtual path used to repair an area partition

Neighbor

The routers running interfaces to which the router is connected

Internal Reach

A 32-bit metric

A bit is added for the up/down transitions resulting from level 2 to level 1 route leaking

IP Prefix

The IP addresses that the router knows about by externally originated interfaces

Metrics

The routing metric used in the IS-IS link-state calculations

hostname

Syntax 
hostname
Context 
show>router>isis
Description 

This command displays the hostname database for the specified IS-IS instance.

To display hostname information for all IS-IS instances, use the show router isis all context.

Output 

The following output is an example of hostname database information, and Table 69 describes the fields.

Output Example
*A:ALU-A show router isis hostname
===============================================================================
Rtr Base ISIS Instance 0 Hostnames 
===============================================================================
System Id                Hostname
-------------------------------------------------------------------------------
2550.0000.0000           7705_custDoc
-------------------------------------------------------------------------------
Hostnames : 1
===============================================================================
Table 69:  Hostname Database Field Descriptions 

Label

Description

System ID

The system ID mapped to the hostname

Hostname

The hostname for the specified system ID

interface

Syntax 
interface [ip-int-name | ip-address] [detail]
Context 
show>router>isis
Description 

This command displays the details of the IS-IS interface, which can be identified by IP address or IP interface name. If neither is specified, in-service interfaces for the specified IS-IS instance are displayed.

To display interface information for all IS-IS instances, use the show router isis all context.

Parameters 
ip-int-name—
displays only the interface identified by this interface name
ip-address—
displays only the interface identified by this IP address
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

detail—
displays detailed information on the interface
Output 

The following outputs are examples of IS-IS interface information:

  1. IS-IS summary interface information (Output Example, Table 70)
  2. IS-IS detailed interface information (Output Example, Table 71)
Output Example
A:ALU-A# show router isis interface 
==============================================================================
Rtr Base ISIS Instance 0 Interfaces 
==============================================================================
Interface                        Level CircID  Oper State   L1/L2 Metric
------------------------------------------------------------------------------
system                           L1L2  1       Up           0/0
isis_interface                   L1L2  30      Down         10/10
------------------------------------------------------------------------------
Interfaces : 2
==============================================================================
A:ALU-A#
Table 70:  Interface Field Descriptions  

Label

Description

Interface

The interface name

Level

The interface level: L1, L2, or L1L2

CircID

The circuit identifier

Oper State

Up: the interface is operationally up

Down: the interface is operationally down

L1/L2 Metric

Interface metric for level 1 and level 2, if none are set to 0

Output Example
A:ALU-A# show router isis interface isis_interface detail
==============================================================================
Rtr Base ISIS Instance 0 Interfaces 
==============================================================================
------------------------------------------------------------------------------
Interface      : isis_interface                  Level Capability: L1L2
Oper State     : Down                            Admin State     : Up
Auth Type      : None
Circuit Id     : 30                              Retransmit Int. : 5
Type           : Broadcast                       LSP Pacing Int. : 100
Mesh Group     : Inactive                        CSNP Int.       : 10
LFA NH Template: None                            Bfd Enabled     : No
Topology       : IPv4-Unicast, IPv6-Unicast
Te Metric      : 0                               Te State        : Down
Admin Groups   : None
Ldp Sync       : outOfService                    Ldp Sync Wait   : Disabled
Ldp Timer State: Disabled                        Ldp Tm Left     : 0
Route Tag      : None                            LFA             : Included
 
  Level         : 1                              Adjacencies     : 0
  Auth Type     : None                           Metric          : 0
  Hello Timer   : 9                              IPv6-Ucast-Met  : 0
  Priority      : 64
  Passive       : No
  SD-Offset     : 0                              SF-Offset       : 0
  Hello Mult.   : 3
 
  Level         : 2                              Adjacencies     : 0
  Auth Type     : None                           Metric          : 0
  Hello Timer   : 9                              IPv6-Ucast-Met  : 0
  Priority      : 64
  Passive       : No
  SD-Offset     : 0                              SF-Offset       : 0
  Hello Mult.   : 3
 
==============================================================================
A:ALU-A#
Table 71:  Interface Detailed Field Descriptions  

Label

Description

Interface

The interface name

Level Capability

The routing level for the IS-IS routing process

Oper State

Up: the interface is operationally up

Down: the interface is operationally down

Admin State

Up: the interface is administratively up

Down: the interface is administratively down

Auth Type

The authentication type for the interface

Circuit Id

The circuit identifier

Retransmit Int.

The length of time, in seconds, that IS-IS will wait before retransmitting an unacknowledged LSP to an IS-IS neighbor

Type

The interface type: point-to-point or broadcast

LSP Pacing Int.

The interval between LSPs sent from this interface

Mesh Group

Indicates whether a mesh group has been configured

CSNP Int.

The time, in seconds, that complete sequence number PDUs (CSNPs) are sent from the interface

LFA NH Template

Indicates whether an LFA next-hop policy template is applied to this interface

BFD Enabled

Indicates whether BFD is enabled or disabled

Topology

The network topology (unicast)

TE Metric

The TE metric configured for this interface. This metric is flooded out in the TE metric sub-TLV in the IS-IS-TE LSPs. Depending on the configuration, either the TE metric value or the native IS-IS metric value is used in CSPF computations.

TE State

The MPLS interface TE status from the IS-IS standpoint

Admin Groups

The bitmap inherited from the MPLS interface that identifies the admin groups to which this interface belongs

Ldp Sync

Specifies whether the IGP-LDP synchronization feature is enabled or disabled on all interfaces participating in the IS-IS routing protocol

Ldp Sync Wait

The time to wait for the LDP adjacency to come up

Ldp Timer State

The state of the LDP sync time left on the IS-IS interface

LDP TM Left

The time left before IS-IS reverts back to advertising normal metrics for this interface

Route Tag

The route tag for this interface

LFA

Indicates whether the interface is included in the LFA SPF calculation

Level

The interface level

Adjacencies

The number of adjacencies for this interface

Auth Type

The authentication type for the interface level

Metric

Indicates whether a metric has been configured for the interface level

Hello Timer

The interval between IS-IS Hello PDUs issued on the interface at this level

IPv6-Ucast-Met

Not applicable

Priority

The priority of the IS-IS interface that is used in an election of the designated router on a multi-access network

Passive

Indicates if passive mode is enabled or disabled; if enabled, the interface is advertised as an IS-IS interface without running the IS-IS protocol

SD-offset

Not applicable

SF-offset

Not applicable

Hello Mult.

Not applicable

lfa-coverage

Syntax 
lfa-coverage
Context 
show>router>isis
Description 

This command displays IS-IS LFA coverage information for the specified IS-IS instance.

To display LFA coverage information for all IS-IS instances, use the show router isis all context.

Output 

The following output is an example of LFA coverage information, and Table 72 describes the fields.

Output Example
A:ALU-A# show router isis lfa-coverage
===============================================================================
Rtr Base ISIS Instance 0 LFA Coverage 
===============================================================================
Topology         Level   Node           IPv4                IPv6
-------------------------------------------------------------------------------
IPV4 Unicast     L1      0/0(0%)        0/0(0%)             0/0(0%)
IPV6 Unicast     L1      0/0(0%)        0/0(0%)             0/0(0%)
IPV4 Multicast   L1      0/0(0%)        0/0(0%)             0/0(0%)
IPV6 Multicast   L1      0/0(0%)        0/0(0%)             0/0(0%)
IPV4 Unicast     L2      0/0(0%)        0/0(0%)             0/0(0%)
IPV6 Unicast     L2      0/0(0%)        0/0(0%)             0/0(0%)
IPV4 Multicast   L2      0/0(0%)        0/0(0%)             0/0(0%)
IPV6 Multicast   L2      0/0(0%)        0/0(0%)             0/0(0%)
===============================================================================
A:ALU-A#
Table 72:  LFA Coverage Field Descriptions  

Label

Description

Topology

The type of network

Level

The IS-IS level in which LFA is enabled

Node

The number of nodes in the level on which LFA is enabled

IPv4

The number of IPv4 interfaces on the nodes on which LFA is enabled

IPv6

The number of IPv6 interfaces on the nodes on which LFA is enabled

mapping-server

Syntax 
mapping-server [prefix ip-address [/mask]] [index index] [level level] [flag {s}]
Context 
show>router>isis
Description 

This command displays IS-IS mapping server information.

Parameters 
ip-address [/mask]
specifies the IP address and subnet mask of a prefix that has received a node-sid in a SID/Label Binding TLV
Values—
ip-address: a.b.c.d. (host bits must be 0)
mask: 0 to 32

 

index—
specifies the node SID index value for the generated SID/Label Binding TLV
Values—
0 to 4294967295

 

level—
specifies a match on the mapping server’s flooding scope for the generated SID/Label Binding TLV
Values—
1, 2, 1/2

 

flag s—
specifies a match on the flooding scope of the generated SID/Label Binding TLV that applies to the entire domain
Output 

The following output is an example of mapping server information.

Output Example
*A:Dut-C# show router isis  mapping-server    
===============================================================================
Rtr Base ISIS Instance 0 Mapping Server
===============================================================================
Index      Prefix             Range Flags Level
-------------------------------------------------------------------------------
1000       10.20.1.4/32       1     -     L1L2
1001       10.20.1.5/32       1     -     L1L2
1002       10.20.1.6/32       1     -     L1L2
-------------------------------------------------------------------------------
No. of Mapping Server Sid-Maps : 3
===============================================================================

prefix-sids

Syntax 
prefix-sids [ipv4-unicast | ipv6-unicast | mt mt-id-number] [ip-prefix[/prefix-length]] [sid sid] [adv-router {system-id | hostname}] [srms | no-srms]
Context 
show>router>isis
Description 

This command displays IS-IS prefix SID information for the specified IS-IS instance.

To display prefix SID information for all IS-IS instances, use the show router isis all context.

Parameters 
ipv4-unicast—
displays information on the IPv4 unicast prefix SIDs
ipv6-unicast—
displays information on the IPv6 unicast prefix SIDs
mt-id-number—
displays information on the multicast tunnel (MT) ID number for a VPRN. The value is always 0.
ip-prefix/prefix-length—
IP prefix and mask length
Values—
ipv4-prefix               a.b.c.d (host bits must be 0)
ipv4-prefix-length    0 to 32
ipv6-prefix               x:x:x:x:x:x:x:x   (eight 16-bit pieces)
                                 x:x:x:x:x:x:d.d.d.d
                                 x: [0..FFFF]H
                               d: [0..255]D
ipv6-prefix-length    0 to 128

 

sid—
displays information related to the specified segment routing ID
Values—
0 to 524287

 

system-id—
displays only the prefix SIDs related to the specified system ID
hostname—
displays only the prefix SIDs related to the specified host
srms | no-srms—
displays information on the IPv4 unicast prefix SIDs segment routing mapping service (SRMS)
Output 

The following output is an example of prefix SIDs information, and Table 73 describes the fields.

Output Example
*A:7705:Dut-A# show router isis  prefix-sids 
===============================================================================
Rtr Base ISIS Instance 0 Prefix/SID Table
===============================================================================
Prefix                            SID        Lvl/Typ    SRMS   AdvRtr
                                                         MT     Flags
-------------------------------------------------------------------------------
10.20.1.1/32                      2001       1/Int.      N     7705:Dut-A
                                                            0       NnP
10.20.1.1/32                      2001       2/Int.      N     7705:Dut-A
                                                            0       NnP
10.20.1.3/32                      2003       1/Int.      N     7705:Dut-C
                                                            0       NnP
10.20.1.3/32                      2003       2/Int.      N     7705:Dut-C
                                                            0       NnP
10.20.1.4/32                      2004       1/Int.      N     7705:Dut-D
                                                            0       NnP
10.20.1.4/32                      2004       2/Int.      N     7705:Dut-D
                                                            0       NnP
10.20.1.22/32                     2002       1/Int.      N     7705:Dut-B
                                                            0       NnP
10.20.1.22/32                     2002       2/Int.      N     7705:Dut-B
                                                            0       NnP
-------------------------------------------------------------------------------
No. of Prefix/SIDs: 8 (4 unique)
-------------------------------------------------------------------------------
SRMS : Y/N  = prefix SID advertised by SR Mapping Server (Y) or not (N)
       S    = SRMS prefix SID is selected to be programmed
Flags: R    = Re-advertisement
       N    = Node-SID
       nP   = no penultimate hop POP 
       E    = Explicit-Null  
       V    = Prefix-SID carries a value  
       L    = value/index has local significance  
===============================================================================
*A:7705:Dut-A#
Table 73:  Prefix SIDs Field Descriptions  

Label

Description

Prefix

The IP prefix for the SID

SID

The segment routing identifier (SID)

Lvl/Typ

The level and type of SR

SRMS

Indicates whether the prefix SID is advertised by the SR mapping service: Y (yes) or N (no)

MT

Not applicable. The value 0 is always displayed.

AdvRtr

The advertised router name

Flags

The flags related to the advertised router:

    R = Re-advertisement

    N = Node-SID

    nP = No penultimate hop POP

    E = Explicit-Null

    V = Prefix-SID carries a value

    L = value/index has local significance

routes

Syntax 
routes [ipv4-unicast | ipv6-unicast | mt mt-id-number] [ip-prefix[/prefix-length]] [alternative] [exclude-shortcut] [detail]
Context 
show>router>isis
Description 

This command displays the routes in the IS-IS routing table for the specified IS-IS instance.

To display route information for all IS-IS instances, use the show router isis all context.

Parameters 
ipv4-unicast—
displays IPv4 unicast parameters
ipv6-unicast—
displays IPv6 unicast parameters
mt-id-number—
displays information on the multicast tunnel (MT) ID number for a VPRN. The value is always 0.
ip-prefix/prefix-length—
IP prefix and mask length
Values—
ipv4-prefix               a.b.c.d (host bits must be 0)
ipv4-prefix-length    0 to 32
ipv6-prefix               x:x:x:x:x:x:x:x   (eight 16-bit pieces)
                                 x:x:x:x:x:x:d.d.d.d
                                 x: [0..FFFF]H
                               d: [0..255]D
ipv6-prefix-length    0 to 128

 

alternative—
displays the level of protection per prefix
exclude-shortcut—
displays routes without shortcuts
detail—
displays detailed information on the route
Output 

The following outputs are examples of IS-IS route information, and Table 74 describes the fields.

Output Example
A:ALU-A# show router isis routes
============================================================================
Rtr Base ISIS Instance 0 Route Table 
============================================================================
Prefix [Flags]                   Metric     Lvl/Typ    Ver.   SysID/Hostname
  NextHop                                              MT      AdminTag/SID[F]
----------------------------------------------------------------------------
10.20.1.2/32                      0          1/Int.     3      ALU-B
   10.0.0.0                                              0         0
10.20.1.3/32 [L]                  10         2/Int.     2      ALU-C
   10.20.3.3                                             0         0
10.20.1.4/32                      10         2/Int.     3      ALU-D
   10.20.4.4                                             0         0
10.20.1.5/32                      20         2/Int.     3      ALU-C
   10.20.3.3                                             0         0
10.20.1.6/32                      20         2/Int.     3      ALU-D
   10.20.4.4                                             0         0
10.20.3.0/24                      10         1/Int.     3      ALU-B
   10.0.0.0                                              0         0
10.20.4.0/24                      10         1/Int.     3      ALU-B
   10.0.0.0                                              0         0
10.20.5.0/24                      20         2/Int.     2      ALU-C
   10.20.3.3                                             0         0
10.20.6.0/24                      20         2/Int.     4      ALU-D
   10.20.4.4                                             0         0
10.20.9.0/24                      20         2/Int.     3      ALU-D
   10.20.4.4                                             0         0
10.20.10.0/24                     30         2/Int.     3      ALU-C
   10.20.3.3                                             0         0
----------------------------------------------------------------------------
No. of Routes : 11
Flags        : L = Loop-Free Alternate nexthop
Alt-Type     : LP = linkProtection, NP = nodeProtection
SID[F]       : R  = Re-advertisement
               N  = Node-SID
               nP = no penultimate hop POP
               E  = Explicit-Null
               V  = Prefix-SID carries a value
               L  = value/index has local significance
============================================================================
A:ALU-A#
A:ALU-A# show router isis routes alternative
============================================================================
Rtr Base ISIS Instance 0 Route Table (alternative) 
============================================================================
Prefix [Flags]                   Metric     Lvl/Typ    Ver.   SysID/Hostname
  NextHop                                              MT      AdminTag/SID[F]
Alt-Nexthop                                            Alt-    Alt-Type
                                                       Metric
----------------------------------------------------------------------------
10.10.1.0/24                      10         1/Int.     3      ALU-A
   10.0.0.0                                              0         0
10.10.2.0/24                      10         1/Int.     4      ALU-A
   10.0.0.0                                              0         0
10.10.4.0/24                      20         1/Int.     5      ALU-B
   10.10.1.2                                             0         0
10.10.5.0/24                      20         1/Int.     5      ALU-C
   10.10.2.3                                             0         0
10.10.9.0/24                      30         1/Int.     6      ALU-B
   10.10.1.2                                             0         0
   10.20.1.5 (LFA)(LSP:RSVP:3)    50          nodeProtection
10.10.10.0/24                     30         1/Int.     11     ALU-E
   10.20.1.5 (LSP:RSVP:3)                                0         0
10.20.1.1/32                      0          1/Int.     1      ALU-A
   10.0.0.0                                              0         0
10.20.1.2/32                      10         1/Int.     4      ALU-B
   10.10.1.2                                             0         0
10.20.1.3/32                      10         1/Int.     5      ALU-C
   10.10.2.3                                             0         0
10.20.1.4/32                      20         1/Int.     5      ALU-B
   10.10.1.2                                             0         0
   10.20.1.5 (LFA)(LSP:RSVP:3)    40           nodeProtection          
10.20.1.5/32                      20         1/Int.     11     Dut-E
   10.20.1.5 (LSP:RSVP:3)                                0         0
10.20.1.6/32                      30         1/Int.     6      Dut-B_Sparrow
   10.10.1.2                                             0          0
   10.10.2.3 (LFA)                30          nodeProtection
----------------------------------------------------------------------------
No. of Routes: 12
Flags        : L = Loop-Free Alternate nexthop
Alt-Type     : LP = linkProtection, NP = nodeProtection
SID[F]       : R  = Re-advertisement
               N  = Node-SID
               nP = no penultimate hop POP
               E  = Explicit-Null
               V  = Prefix-SID carries a value
               L  = value/index has local significance
============================================================================
A:ALU-A#
Table 74:  Routing Table Field Descriptions  

Label

Description

Prefix (Flags)

The route prefix and mask, and the L/LFA flag (if applicable)

Metric

The metric of the route

Lvl/Typ

The level (1 or 2) and the route type (internal or external)

Ver.

The SPF version that generated the route

SysID/Hostname

The hostname for the specific system ID

MT

Not applicable. The value 0 is always displayed.

NextHop

The system ID of the next hop (or the hostname, if possible)

AdminTag/SID[F]

The flags related to the SID:

    R = Re-advertisement

    N = Node SID

    nP = No penultimate hop POP

    E = Explicit null

    V = Prefix-SID carries a value

    L = Value/index has local significance

Alt-Nexthop

The backup next hop

Alt-Metric

The metric of the backup route

Alt-Type

The type of backup route

LP = Link protection

NP = Node protection

spf-log

Syntax 
spf-log [detail]
Context 
show>router>isis
Description 

This command displays the last 20 SPF events for the specified IS-IS instance.

To display SPF log information for all IS-IS instances, use the show router isis all context.

Parameters 
detail—
displays detailed information about the SPF events
Output 

The following output is an example of SPF events, and Table 75 describes the fields.

Output Example
A:ALU-A# show router isis spf-log
===============================================================================
Rtr Base ISIS Instance 0 SPF Log 
===============================================================================
When                 Duration     L1 Nodes   L2 Nodes   Event Count  Type
-------------------------------------------------------------------------------
05/23/2018 18:41:06  <0.01s       1          1          1            Reg
05/23/2018 18:41:06  <0.01s       -          -          -            Lfa
-------------------------------------------------------------------------------
Log Entries: 2
===============================================================================
*A:Sar18 Dut-B>show>router# isis spf-log detail
===============================================================================
Rtr Base ISIS Instance 0 SPF Log
===============================================================================
When       : 05/23/2018 18:41:06             Duration    : <0.01s
L1 Nodes   : 1                               L2 Nodes    : 1
Trigger LSP: None                            Event Count : 1
SPF Type   : Reg
Reason     : LFACHANGED
When       : 05/23/2018 18:41:06             Duration    : <0.01s
L1 Nodes   : -                               L2 Nodes    : -
Trigger LSP: None                            Event Count : -
SPF Type   : Lfa
Reason     : LFACHANGED
===============================================================================
Table 75:  SPF Log Field Descriptions  

Label

Description

When

The timestamp when the SPF run started on the system

Duration

The time (in hundredths of seconds) required to complete the SPF run

L1 Nodes

The number of level 1 nodes involved in the SPF run

L2 Nodes

The number of level 2 nodes involved in the SPF run

Trigger LSP

The LSP that triggered the SPF run

Event Count

The number of SPF events that triggered the SPF calculation

Type

SPF Type

The SPF type: Reg (regular) or Lfa (Loopfree-Alternate)

Reason

The reason(s) for the SPF run:

  ADMINTAGCHANGED: An administrative tag changed

  DBCHANGED: The LSP database was cleared by an                            administrator

  ECMPCHANGED: An ECMP path changed

  LFACHANGED: The LFS changed

  LSPCONTENT: The content of an LSP changed

  LSPEXPIRED: An LSP expired

  MANUALREQ: An SPF calculation was requested by an                               administrator

  NEWADJ: An adjacency changed

  NEWAREA: An area changed

  NEWLSP: A new LSP was received

  NEWMETRIC: A prefix metric changed

  NEWNLPID: The routed protocols (IPv4 or IPv6) changed

  NEWPREF: The external route preference changed

  NEWREACH: A prefix changed

  RESTART: The graceful restart exited

  TUNNELCHANGED: An MPLS tunnel changed

Log Entries

The total number of log entries

statistics

Syntax 
statistics
Context 
show>router>isis
Description 

This command displays information about IS-IS traffic statistics for the specified IS-IS instance.

To display statistics information for all IS-IS instances, use the show router isis all context.

Output 

The following output is an example of IS-IS statistical information, and Table 76 describes the fields.

Output Example
A:ALU-A# show router isis statistics
===============================================================================
Rtr Base ISIS Instance 0 Statistics
===============================================================================
ISIS Instance     : 0                       
Purge Initiated   : 0                       LSP Regens.    : 39
SID SRGB errors   : 0                       SID dupl errors: 0
 
CSPF Statistics
Requests          : 0                       Request Drops  : 0
Paths Found       : 0                       Paths Not Found: 0
 
SPF Statistics
SPF Runs          : 1
 Last scheduled   : 05/23/2018 18:41:05
Partial SPF Runs  : 3 
 Last scheduled   : 05/23/2018 18:41:03
 
LFA Statistics
LFA Runs : 1
 Last scheduled   : 05/23/2018 18:41:06
Partial LFA Runs  : 0
 
RLFA Statistics
RLFA Runs         : 0
 
TI-LFA Statistics
TI-LFA Runs         : 0
 
-------------------------------------------------------------------------------
PDU Type   Received   Processed  Dropped    Sent       Retransmitted
-------------------------------------------------------------------------------
LSP        0          0          0          0          0
IIH        0          0          0          0          0
CSNP       0          0          0          0          0
PSNP       0          0          0          0          0
Unknown    0          0          0          0          0
===============================================================================
A:ALU-A# 
Table 76:  IS-IS Statistics Field Descriptions  

Label

Description

ISIS Instance

The IS-IS instance

Purge Initiated

The number of times that purges have been initiated

LSP Regens

The number of LSP regenerations

SID SRGB errors

The number of SIDs received that are outside of the Segment Routing Global Block (SRGB) label range

SID dupl errors

The number of duplicate SIDs received from IS-IS nodes in the network

CSPF Statistics

Requests

The number of CSPF requests made to the protocol

Request Drops

The number of CSPF requests dropped

Paths Found

The number of responses to CSPF requests for which paths satisfying the constraints were found

Paths Not Found

The number of responses to CSPF requests for which paths not satisfying the constraints were found

SPF Statistics

SPF Runs

The number of times that SPF calculations have been made

Last scheduled

The timestamp of the last SPF run

Partial SPF Runs

The total number of partial SPF runs

Last scheduled

The timestamp of the last partial SPF run

LFA Statistics

LFA Runs

The total number of incremental LFA SPF runs triggered by new or updated LSPs

Last scheduled

The timestamp of the last SPF run

Partial LFA Runs

The total number of partial LFA SPF runs triggered by new or updated LSPs

RLFA Statistics

RLFA Runs

The total number of incremental remote LFA SPF runs triggered by new or updated LSPs

TI-LFA Statistics

TI-LFA Runs

The total number of incremental topology-independent LFA SPF runs triggered by new or updated LSPs

Other Statistics

PDU Type

The PDU (packet) type

Received

The number of LSPs received by this instance of the protocol

Processed

The number of LSPs processed by this instance of the protocol

Dropped

The number of LSPs dropped by this instance of the protocol

Sent

The number of LSPs sent out by this instance of the protocol

Retransmitted

The number of LSPs that had to be retransmitted by this instance of the protocol

status

Syntax 
status
Context 
show>router>isis
Description 

This command displays the general status of IS-IS for the specified IS-IS instance.

To display statistics information for all IS-IS instances, use the show router isis all context.

Output 

The following output is an example of IS-IS status information, and Table 77 describes the fields.

Output Example
*A:Sar18 Dut-B>show>router# isis status
===============================================================================
Rtr Base ISIS Instance 0 Status
===============================================================================
ISIS Oper System Id  : 0100.1001.0001
ISIS Cfg Router Id   : 0.0.0.0
ISIS Oper Router Id  : 10.0.0.0
ASN                  : 0
Admin State          : Up
Oper State           : Up
Ipv4 Routing         : Enabled
Ipv6 Routing         : Disabled
Last Enabled         : 05/23/2018 18:41:05
Level Capability     : L1L2
Authentication Check : True
Auth Keychain        : Disabled
Authentication Type  : None
CSNP-Authentication  : Enabled
HELLO-Authentication : Enabled
PSNP-Authentication  : Enabled
Traffic Engineering  : Disabled
Overload-On-Boot Tim*: 0
LSP Lifetime         : 1200
LSP Wait             : 5000 ms (Max)   10 ms (Initial)   1000 ms (Second)
LSP MTU Size         : 1492  (Config)
L1 LSP MTU Size      : 1492  (Config)  1492  (Oper)
L2 LSP MTU Size      : 1492  (Config)  1492  (Oper)
Adjacency Check      : loose
L1 Auth Keychain     : Disabled
L1 Auth Type         : none
L1 CSNP-Authenticati*: Enabled
L1 HELLO-Authenticat*: Enabled
L1 PSNP-Authenticati*: Enabled
L1 Preference        : 15
L1 Ext. Preference   : 160
L1 Wide Metrics      : Disabled
L1 LSDB Overload     : Disabled
L1 LSPs              : 1
L1 Default Metric    : 10
L1 IPv6 Def Metric   : 10
L1 Mcast IPv4 Def Me*: 10
L1 Mcast IPv6 Def Me*: 10
L1 Adv Router Cap    : Enabled
Last SPF             : 05/23/2018 18:41:06
SPF Wait             : 10000 ms (Max)   1000 ms (Initial)   1000 ms (Second)
Area Addresses       : None
Total Exp Routes(L1) : 0
IID TLV              : Disabled
All-L1-MacAddr (Cfg) : 01:80:c2:00:00:14
L2 Auth Keychain     : Disabled
L2 Auth Type         : none
L2 CSNP-Authenticati*: Enabled
L2 HELLO-Authenticat*: Enabled
L2 PSNP-Authenticati*: Enabled
L2 Preference        : 18
L2 Ext. Preference   : 165
L2 Wide Metrics      : Disabled
L2 LSDB Overload     : Disabled
L2 LSPs              : 1
L2 Default Metric    : 10
L2 IPv6 Def Metric   : 10
L2 Mcast IPv4 Def Me*: 10
L2 Mcast IPv6 Def Me*: 10
L2 Adv Router Cap    : Enabled
Export Policies      : None
LFA Policies         : None
Ignore Attached Bit  : Disabled
Suppress Attached Bit: Disabled
Default Route Tag    : None
Rib Prio List High   : None
Rib Prio Tag High    : None
Ldp Sync Admin State : Up
LDP-over-RSVP        : Disabled
RSVP-Shortcut        : Disabled
Advertise-Tunnel-Link: Disabled
Export Limit         : 0
Exp Lmt Log Percent  : 0
Total Exp Routes(L2) : 0
All-L2-MacAddr (Cfg) : 01:80:c2:00:00:15
Loopfree-Alternate   : Enabled
Remote-LFA           : Disabled
Max PQ Cost          : 4261412864
TI-LFA               : Disabled
Max SR FRR Labels    : 2
L1 LFA               : Included
L2 LFA               : Included
Advertise Router Cap : Disabled
Hello Padding        : Disabled
L1 Hello Padding     : Disabled
L2 Hello Padding     : Disabled
Ignore Lsp Errors    : Disabled
Reference Bandwidth  : 0
Ucast Import Disable : None
Segment Routing      : Disabled
Mapping Server       : Disabled
Purge Originator Id  : Disabled
Entropy Label        : Enabled
Override ELC         : Enabled
===============================================================================
* indicates that the corresponding row element may have been truncated.
Table 77:  IS-IS Status Field Descriptions  

Label

Description

ISIS Oper System Id

The operational system ID mapped to the hostname

ISIS Cfg Router Id

The router ID configured for the router

ISIS Oper Router Id

The operational router ID

ASN

The autonomous system (AS) number

Admin State

Up: IS-IS is administratively up

Down: IS-IS is administratively down

Oper State

Up: IS-IS is operationally up

Down: IS-IS is operationally down

IPv4 Routing

Enabled: IPv4 routing is enabled

Disabled: IPv4 routing is disabled

IPv6 Routing

Enabled: IPv6 routing is enabled

Disabled: IPv6 routing is disabled

Last Enabled

The date and time that IS-IS was last enabled on the router

Level Capability

The routing level for the IS-IS routing process

Authentication Check

True: all IS-IS mismatched packets are rejected

False: authentication is performed on received IS-IS protocol packets but mismatched packets are not rejected

Auth Keychain

Enabled: an authentication keychain is enabled

Disabled: an authentication keychain is disabled

Authentication Type

The method of authentication used to verify the authenticity of packets sent by neighboring routers on an IS-IS interface

CSNP-Authentication

Indicates whether authentication of CSNP packets is enabled

HELLO-Authentication

Indicates whether authentication of Hello packets is enabled

PSNP Authentication

Indicates whether authentication of PSNP packets is enabled

Traffic Engineering

Enabled: TE is enabled for the router

Disabled: TE is disabled; TE metrics are not generated and are ignored when received by this node

Overload-on-Boot Tim

The length of time that IS-IS is in the overload state upon boot-up

LSP Lifetime

The length of time that the LSPs originated by the router are to be considered valid by other routers in the domain

LSP Wait

The length of time that the router will generate the first, second, and subsequent LSPs

LSP MTU Size

The MTU size for LSPs (configured and operational)

L1 LSP MTU Size

The MTU size for level 1 LSPs (derived from the LSP MTU size)

L2 LSP MTU Size

The MTU size for level 2 LSPs (derived from the LSP MTU size)

Adjacency Check

Type of adjacency check – always “loose”

L1 Auth Keychain

Enabled: an authentication keychain is enabled on the level 1 router

Disabled: an authentication keychain is disabled on the level 1 router

L1 Auth Type

The method of authentication used to verify the authenticity of packets sent by neighboring routers to an IS-IS level 1 router

L1 CSNP-Authentication

Indicates whether authentication of CSNP packets is enabled on the level 1 router

L1 HELLO-Authentication

Indicates whether authentication of Hello packets is enabled on the level 1 router

L1 PSNP Authentication

Indicates whether authentication of PSNP packets is enabled on the level 1 router

L1 Preference

The preference level for level 1 internal routes

L1 Ext. Preference

The preference level for level 1 external routes

L1 Wide Metrics

Indicates whether wide metrics are enabled or disabled for level 1 routers

L1 LSDB Overload

Indicates whether link-state database overload is enabled or disabled for level 1 routers

L1 LSPs

Number of LSPs sent on the level 1 router interface

L1 Default Metric

The default metric for the level 1 router interface

L1 IPv6 Def Metric

The default metric for the level 1 router IPv6 interface

L1 Mcast IPv4 Def Metric

The default metric for the level 1 multicast IPv4 interface

L1 Mcast IPv6 Def Metric

The default metric for the level 1 multicast IPv6 interface

L1 Adv Router Cap

The level 1 advertised router capacity

Last SPF

Date and time that the last SPF calculation was performed

SPF Wait

Length of time that the first, second, and subsequent SPF calculations are initiated after a topology change occurs

Area Addresses

The number of area addresses (area IDs) configured for the router

Total Exp Routes(L1)

Total number of routes exported from the routing table to a level 1 router

IID TLV

Indicates whether the IID TLV is enabled or disabled for this IS-IS instance

All-L1-MacAddr

Indicates the MAC address used by this level 1 router interface. For the default (base) IS-IS instance, the MAC address is 01:80:c2:00:00:14. For all other IS-IS instances, the MAC address is 01:00:5e:90:00:02.

L2 Auth Keychain

Enabled: an authentication keychain is enabled on the level 2 router

Disabled: an authentication keychain is disabled on the level 2 router

L2 Auth Type

The method of authentication used to verify the authenticity of packets sent by neighboring routers to an IS-IS level 2 router

L2 CSNP-Authentication

Indicates whether authentication of CSNP packets is enabled on the level 2 router

L2 HELLO-Authentication

Indicates whether authentication of Hello packets is enabled on the level 2 router

L2 PSNP Authentication

Indicates whether authentication of PSNP packets is enabled on the level 2 router

L2 Preference

The preference level for level 2 internal routes

L2 Ext. Preference

The preference level for level 2 external routes

L2 Wide Metrics

Indicates whether wide metrics are enabled or disabled for level 2 routers

L2 LSDB Overload

Indicates whether link-state database overload is enabled or disabled for level 2 routers

L2 LSPs

Number of LSPs sent on the level 2 router interface

L2 Default Metric

The default metric for the level 2 router interface

L2 IPv6 Def Metric

The default metric for the level 2 router IPv6 interface

L2 Mcast IPv4 Def Metric

The default metric for the level 2 multicast IPv4 interface

L2 Mcast IPv6 Def Metric

The default metric for the level 2 multicast IPv6 interface

L2 Adv Router Cap

The level 2 advertised router capacity

Export Policies

Indicates if export policies are applied to the router

LFA Policies

Lists the defined LFA policies

Ignore Attached Bit

Indicates whether the ATT bit is ignored on received level 1 LSPs and therefore the level 1 router does not install default routes

Suppress Attached Bit

Indicates whether the ATT bit is suppressed on originating level 1 LSPs to prevent level 1 routers from installing default routes

Default Route Tag

n/a

Rib Prio List High

n/a

Rib Prio Tag High

n/a

LDP Sync Admin State

Indicates whether the IGP-LDP synchronization feature is enabled or disabled on all interfaces participating in the IS-IS routing protocol

LDP-over-RSVP

Indicates whether LDP over RSVP processing is enabled in IS-IS

RSVP-Shortcut

Indicates whether RSVP-TE shortcuts (IGP shortcuts) are enabled

Advertise-Tunnel-Link

Indicates whether forwarding adjacencies are enabled

Export Limit

The maximum number of routes that can be exported into IS-IS from the route table

Exp Lmt Log Percent

The percentage of the maximum number of routes at which a warning message and SNMP notification is sent

Total Exp Routes(L2)

Total number of routes exported from the routing table to a level 2 router

All-L2-MacAddr

Indicates the MAC address used by this level 2 router interface. For the default (base) IS-IS instance, the MAC address is 01:80:c2:00:00:15. For all other IS-IS instances, the MAC address is 01:00:5e:90:00:03.

Loopfree-Alternate

Indicates whether LFA is enabled

Remote-LFA

Indicates if remote LFA is enabled or disabled under the loopfree-alternate command

Max PQ Cost

Indicates the configured maximum PQ cost under the loopfree-alternate command

TI-LFA

Indicates if TI-LFA is enabled or disabled under the loopfree-alternate command

Max SR FRR Labels

The maximum number of segment routing FRR labels

L1 LFA

Indicates whether interfaces in this level are included in the LFA SPF calculation

L2 LFA

Indicates whether interfaces in this level are included in the LFA SPF calculation

Advertise Router Cap

Indicates whether router capabilities are enabled

Hello Padding

Indicates whether hello padding is enabled

L1 Hello Padding

Indicates whether level 1 hello padding is enabled

L2 Hello Padding

Indicates whether level 2 hello padding is enabled

Ignore Lsp Errors

Indicates whether ignoring LSP errors is enabled

Reference Bandwidth

Indicates configured reference bandwidth for calculating interface metrics

Ucast Import Disable

Indicates whether ISIS is configured to import its routes into RPF RTM (the multicast routing table)

Segment Routing

Indicates whether segment routing is enabled

Mapping Server

Indicates whether server mapping is enabled

Purge Originator Id

Indicates whether the Purge Originator Identification (POI) TLV is enabled

Entropy Label

Indicates whether entropy label is enabled

Override ELC

Indicates whether entropy label capability is enabled for BGP tunnels

summary-address

Syntax 
summary-address [ip-prefix[/prefix-length]]
Context 
show>router>isis
Description 

This command displays IS-IS summary addresses for the specified IS-IS instance.

To display statistics information for all IS-IS instances, use the show router isis all context.

Parameters 
ip-prefix/prefix-length—
IP prefix and mask length
Values—
ipv4-prefix               a.b.c.d (host bits must be 0)
ipv4-prefix-length    0 to 32
ipv6-prefix               x:x:x:x:x:x:x:x   (eight 16-bit pieces)
                                x:x:x:x:x:x:d.d.d.d
                                 x: [0..FFFF]H
                                d: [0..255]D
ipv6-prefix-length    0 to 128

 

Output 

The following output is an example of IS-IS summary address information, and Table 78 describes the fields.

Output Example
A:ALU-A# show router isis summary-address
===============================================================================
Rtr Base ISIS Instance 0 Summary Address
===============================================================================
Address                                           Level               Tag
10.0.0.0/8                                         L1                  None   
10.3.3.3/32                                        L2                  None   
-------------------------------------------------------------------------------
A:ALU-A# 
Table 78:  Summary Address Field Descriptions  

Label

Description

Address

The IP address

Level

The IS-IS level from which the prefix should be summarized

Tag

The IS-IS tag (if any) assigned to this summary address

topology

Syntax 
topology [detail] [lfa]
Context 
show>router>isis
Description 

This command displays IS-IS topology information for the specified IS-IS instance.

To display statistics information for all IS-IS instances, use the show router isis all context.

Parameters 
detail—
displays detailed topology information
lfa—
displays LFA information
Output 

The following outputs are examples of IS-IS topology information, and Table 79 describes the fields.

Output Example
A:ALU-A# show router isis topology 
===============================================================================
Rtr Base ISIS Instance 0 Topology Table 
===============================================================================
Node                                Interface                  Nexthop
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 1
-------------------------------------------------------------------------------
7705:ALU-A.00                       ip-10.20.1.2               7705:ALU-A
7705:ALU-A.00                       ip-10.20.3.2               7705:ALU-A
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 2
-------------------------------------------------------------------------------
7705:ALU-C.00                       ip-10.20.4.1               7705:ALU-C
7705:ALU-C.00                       ip-10.20.6.1               7705:ALU-C
7705:ALU-D.00                       ip-10.20.4.1               7705:ALU-C
7705:ALU-D.00                       ip-10.20.6.1               7705:ALU-C
7705:ALU-D.01                       ip-10.20.4.1               7705:ALU-C
7705:ALU-D.01                       ip-10.20.6.1               7705:ALU-C
7705:ALU-F.00                       ip-10.20.13.1              7705:ALU-F
===============================================================================
A:ALU-A# show router isis topology detail 
===============================================================================
Rtr Base ISIS Instance 0 Topology Table 
===============================================================================
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 1
-------------------------------------------------------------------------------
Node      : 7705:ALU-A.00                    Metric      : 10
Interface : ip-10.20.1.2                     SNPA        : none
Nexthop   : 7705:ALU-A 
 
Node      : 7705:ALU-A.00                    Metric      : 10
Interface : ip-10.20.3.2                     SNPA        : none
Nexthop   : 7705:ALU-A 
 
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 2
-------------------------------------------------------------------------------
Node      : 7705:ALU-C.00                    Metric      : 10
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C                       
 
Node      : 7705:ALU-C.00                    Metric      : 10
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.00                    Metric      : 20
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.00                    Metric      : 20
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.01                    Metric      : 20
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.01                    Metric      : 20
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-F.00                    Metric      : 10
Interface : ip-10.20.13.1                    SNPA        : none
Nexthop   : 7705:ALU-F 
 
===============================================================================
A:ALU-A#
*A:Sar18 Dut-B>show>router# isis topology lfa
===============================================================================
Rtr Base ISIS Instance 0 Topology Table
===============================================================================
Node                                Interface                  Nexthop
                                       LFA Interface              LFA Nexthop
-------------------------------------------------------------------------------
No Matching Entries
===============================================================================
*A:Sar18 Dut-B>show>router#
A:ALU-A# show router isis topology lfa detail
===============================================================================
Rtr Base ISIS Instance 0 Topology Table
===============================================================================
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 1
-------------------------------------------------------------------------------
Node      : 7705:ALU-A.00                    Metric      : 10
Interface : ip-10.20.1.2                     SNPA        : none
Nexthop   : 7705:ALU-A 
 
Node      : 7705:ALU-A.00                    Metric      : 10
Interface : ip-10.20.3.2                     SNPA        : none
Nexthop   : 7705:ALU-A 
 
Node      : 7705:ALU-D.00                    Metric      : 20
Interface : ip-10.20.6.1                     SNPA        : 00:00:00:00:00:02
Nexthop   : 7705:ALU-B
 
LFA intf  : to_ALU-C1                        LFA Metric  : 40
LFA nh    : 7705:ALU-E                       LFA type    : nodeProtection
 
-------------------------------------------------------------------------------
IS-IS IP paths (MT-ID 0),   Level 2
-------------------------------------------------------------------------------
Node      : 7705:ALU-C.00                    Metric      : 10
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C                       
 
Node      : 7705:ALU-C.00                    Metric      : 10
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.00                    Metric      : 20
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.00                    Metric      : 20
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.01                    Metric      : 20
Interface : ip-10.20.4.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-D.01                    Metric      : 20
Interface : ip-10.20.6.1                     SNPA        : none
Nexthop   : 7705:ALU-C 
 
Node      : 7705:ALU-F.00                    Metric      : 10
Interface : ip-10.20.13.1                    SNPA        : none
Nexthop   : 7705:ALU-F 
 
===============================================================================
A:ALU-A#
Table 79:  IS-IS Topology Field Descriptions  

Label

Description

Node

The IP address

Interface

The interface name

Nexthop

The next-hop IP address

Metric

The route metric for the route

SNPA

The subnetwork points of attachment (SNPA) where a router is physically attached to a subnetwork

LFA intf

LFA interface

The LFA interface name

LFA Metric

The route metric for the LFA backup route

LFA nh

LFA nexthop

The LFA next hop

LFA type

The LFA protection type: link protection or node protection

5.11.2.3. Clear Commands

isis

Syntax 
isis [isis-instance]
Context 
clear>router
Description 

This command enables the context to clear IS-IS information.

Parameters 
isis-instance—
the IS-IS instance ID. If no isis-instance is specified, instance 0 is used.
Values—
0 to 31

 

adjacency

Syntax 
adjacency [system-id]
Context 
clear>router>isis
Description 

This command clears and resets the entries from the IS-IS adjacency database.

Parameters 
system-id—
6-octet system identifier in the form xxxx.xxxx.xxxx

database

Syntax 
database [system-id]
Context 
clear>router>isis
Description 

This command removes the entries from the IS-IS link-state database that contains information about PDUs.

Parameters 
system-id—
6-octet system identifier in the form xxxx.xxxx.xxxx

export

Syntax 
export
Context 
clear>router>isis
Description 

This command re-evaluates the route policies for IS-IS.

spf-log

Syntax 
spf-log
Context 
clear>router>isis
Description 

This command clears the SPF log.

statistics

Syntax 
statistics
Context 
clear>router>isis
Description 

This command clears and resets all IS-IS statistics.

5.11.2.4. Debug Commands

isis

Syntax 
isis [isis-instance]
Context 
debug>router
Description 

This command enables the context to debug IS-IS information.

Parameters 
isis-instance—
the IS-IS instance ID. If no isis-instance is specified, instance 0 is used.
Values—
0 to 31

 

adjacency

Syntax 
[no] adjacency [ip-int-name | ip-address | nbr-system-id]
Context 
debug>router>isis
Description 

This command enables or disables debugging for IS-IS adjacency.

Parameters 
ip-int-name—
debugs only adjacencies with the specified interface
ip-address—
debugs only adjacencies with the specified IP address
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

nbr-system-id—
debugs only the adjacency with the specified system ID

cspf

Syntax 
[no] cspf
Context 
debug>router>isis
Description 

This command enables or disables debugging for an IS-IS constraint-based shortest path first (CSPF).

interface

Syntax 
interface [ip-int-name | ip-address]
no interface
Context 
debug>router>isis
Description 

This command enables or disables debugging for an IS-IS interface.

Parameters 
ip-int-name—
the IP interface name. An interface name cannot be in the form of an IP address. Interface names can be any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.
ip-address—
the interface IP address
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

leak

Syntax 
leak [ip-address]
no leak
Context 
debug>router>isis
Description 

This command enables or disables debugging for IS-IS leaks.

Parameters 
ip-address—
the IP address to debug for IS-IS leaks
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

lsdb

Syntax 
[no] lsdb [level-number] [system-id | lsp-id]
Context 
debug>router>isis
Description 

This command enables or disables debugging for the IS-IS link-state database.

Parameters 
level-number—
1 or 2
system-id—
6-octet system identifier in the form xxxx.xxxx.xxxx
lsp-id—
the hostname (38 characters maximum)

misc

Syntax 
[no] misc
Context 
debug>router>isis
Description 

This command enables or disables debugging for miscellaneous IS-IS events.

packet

Syntax 
[no] packet [packet-type] [ip-int-name | ip-address | ipv6-address] [detail]
Context 
debug>router>isis
Description 

This command enables or disables debugging for IS-IS packets.

Parameters 
packet-type—
the IS-IS packet type to debug
Values—
ptop-hello | l1-hello | l2-hello | l1-psnp | l2-psnp |  l1-csnp | l2- csnp | l1-lsp | l2-lsp

 

ip-int-name—
the IP interface name. An interface name cannot be in the form of an IP address. Interface names can be any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.
ip-address—
the IPv4 address to debug
Values—
a.b.c.d

 

ipv6-address—
the IPv6 address to debug
Values—
x:x:x:x:x:x:x:x (eight 16-bit pieces) x:x:x:x:x:x:d.d.d.d x: [0 to FFFF]H d: [0 to 255]D

 

detail—
provides detailed debugging information

rtm

Syntax 
rtm [ip-address]
no rtm
Context 
debug>router>isis
Description 

This command enables or disables debugging for the IS-IS routing table manager.

Parameters 
ip-address—
the IP address to debug
Values—
ipv4-address:          a.b.c.d
ipv6-address:          x:x:x:x:x:x:x:x (eight 16-bit pieces)                                 x:x:x:x:x:x:d.d.d.d                                 x: [0..FFFF]H                                 d: [0..255]D

 

spf

Syntax 
[no] spf [level-number] [system-id]
Context 
debug>router>isis
Description 

This command enables or disables debugging for IS-IS SPF calculations.

Parameters 
level-number—
1 or 2
system-id—
6-octet system identifier in the form xxxx.xxxx.xxxx

5.11.2.5. Monitor Commands

isis

Syntax 
isis [isis-instance]
Context 
monitor>router
Description 

This command enables the context to monitor IS-IS information.

Parameters 
isis-instance—
the IS-IS instance ID. If no isis-instance is specified, instance 0 is used.
Values—
0 to 31

 

statistics

Syntax 
statistics [interval seconds] [repeat repeat] [absolute | rate]
Context 
monitor>router>isis
Description 

This command enables monitoring statistics for IS-IS instances.

Parameters 
seconds—
specifies the interval for each display in seconds
Values—
3 to 60

 

Default—
10
repeat—
specifies the number of times the command is repeated
Values—
1 to 999

 

Default—
10
absolute—
specifies that raw statistics are displayed, without processing. No calculations are performed on the delta or rate statistics.
rate—
specifies the rate per second for each statistic instead of the delta
Output 

The following output is an example of statistics information for a router IS-IS instance.

Output Example
A:7705custDoc:Sar18>monitor>router>isis# statistics
===============================================================================
ISIS Statistics
===============================================================================
-------------------------------------------------------------------------------
At time t = 0 sec (Base Statistics)
-------------------------------------------------------------------------------
ISIS Instance     : 0                       SPF Runs       : 0
Purge Initiated   : 0                       LSP Regens.    : 73
CSPF Statistics
Requests          : 0                       Request Drops  : 0
Paths Found       : 0                       Paths Not Found: 0
-------------------------------------------------------------------------------
PDU Type   Received   Processed  Dropped    Sent       Retransmitted
-------------------------------------------------------------------------------
LSP        0          0          0          0          0
IIH        0          0          0          0          0
CSNP       0          0          0          0          0
PSNP       0          0          0          0          0
Unknown    0          0          0          0          0
-------------------------------------------------------------------------------
At time t = 10 sec (Mode: Delta)
-------------------------------------------------------------------------------
ISIS Instance     : 0                       SPF Runs       : 0
Purge Initiated   : 0                       LSP Regens.    : 0
CSPF Statistics
Requests          : 0                       Request Drops  : 0
Paths Found       : 0                       Paths Not Found: 0
-------------------------------------------------------------------------------
PDU Type   Received   Processed  Dropped    Sent       Retransmitted
-------------------------------------------------------------------------------
LSP        0          0          0          0          0
IIH        0          0          0          0          0
CSNP       0          0          0          0          0
PSNP       0          0          0          0          0
Unknown    0          0          0          0          0
-------------------------------------------------------------------------------
At time t = 20 sec (Mode: Delta)
-------------------------------------------------------------------------------
ISIS Instance     : 0                       SPF Runs       : 0
Purge Initiated   : 0                       LSP Regens.    : 0
CSPF Statistics
Requests          : 0                       Request Drops  : 0
Paths Found       : 0                       Paths Not Found: 0
-------------------------------------------------------------------------------
PDU Type   Received   Processed  Dropped    Sent       Retransmitted
-------------------------------------------------------------------------------
LSP        0          0          0          0          0
IIH        0          0          0          0          0
CSNP       0          0          0          0          0
PSNP       0          0          0          0          0
Unknown    0          0          0          0          0
-------------------------------------------------------------------------------