BGP commands

bgp

Syntax

[no] bgp

Context

config>service>vprn

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables the BGP protocol with the VPRN service.

The no form of this command disables the BGP protocol from the specific VPRN service.

Default

no bgp

advertise-inactive

Syntax

[no] advertise-inactive

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables or disables the advertising of inactive BGP routers to other BGP peers.

By default, BGP only advertises BGP routes to other BGP peers if a specific BGP route is chosen by the route table manager as the most preferred route within the system and is active in the forwarding plane. This command allows system administrators to advertise a BGP route even though it is not the most preferred route within the system for a specific destination.

Default

no advertise-inactive

aggregator-id-zero

Syntax

[no] aggregator-id-zero

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command sets the router ID in the BGP aggregator path attribute to zero when BGP aggregates routes. This prevents different routers within an AS from creating aggregate routes that contain different AS paths.

When BGP is aggregating routes, it adds the aggregator path attribute to the BGP update messages. By default, BGP adds the AS number and router ID to the aggregator path attribute.

When this command is enabled, BGP adds the router ID to the aggregator path attribute. This command is used at the group level to revert to the value defined under the global level, while this command is used at the neighbor level to revert to the value defined under the group level.

The no form of this command used at the global level reverts to default where BGP adds the AS number and router ID to the aggregator path attribute.

The no form of this command used at the group level reverts to the value defined at the group level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

no aggregator-id-zero

always-compare-med

Syntax

always-compare-med {zero | infinity}

no always-compare-med

Context

config>service>vprn>bgp

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command specifies how the Multi-Exit Discriminator (MED) path attribute is used in the BGP route selection process. The MED attribute is always used in the route selection process regardless of the peer AS that advertised the route. This parameter determines what MED value is inserted in the RIB-IN. If this parameter is not configured, only the MEDs of routes that have the same peer ASs are compared.

The no form of this command removes the parameter from the configuration.

Default

no always-compare-med

Parameters

zero

Specifies that for routes learned without a MED attribute that a zero (0) value is used in the MED comparison. The routes with the lowest metric are the most preferred.

infinity

Specifies for routes learned without a MED attribute that a value of infinity (4294967295) is used in the MED comparison. This in effect makes these routes the least desirable.

as-path-ignore

Syntax

[no] as-path-ignore

Context

config>service>vprn>bgp

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command determines whether the AS path is used to determine the best BGP route.

If this option is present, the AS paths of incoming routes are not used in the route selection process.

The no form of this command removes the parameter from the configuration.

Default

no as-path-ignore

as-override

Syntax

[no] as-override

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command replaces all instances of the peer's AS number with the local AS number in a BGP route's AS_PATH.

This command breaks the BGP's loop detection mechanism. It should be used carefully.

Default

not enabled

authentication-key

Syntax

authentication-key [authentication-key | hash-key] [hash | hash2]

no authentication-key

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the BGP authentication key.

Authentication is performed between neighboring routers before setting up the BGP session by verifying the password. Authentication is performed using the MD-5 message-based digest. The authentication key can be any combination of letters or numbers from 1 to 16.

The no form of this command removes the authentication password from the configuration and effectively disables authentication.

Default

Authentication is disabled and the authentication password is empty.

Parameters

authentication-key

Specifies the authentication key. The key can be any combination of ASCII characters up to 255 characters (unencrypted). If spaces are used in the string, enclose the entire string in quotation marks (‟ ”).

hash-key

Specifies the hash key. The key can be any combination of ASCII characters up to 342 characters (encrypted). If spaces are used in the string, enclose the entire string in quotation marks (‟ ”).

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

hash

Specifies 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 the key is entered in a more complex encrypted form. If the hash2 parameter is not used, the less encrypted hash form is assumed.

auth-keychain

Syntax

auth-keychain name

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the BGP authentication key for all peers.

The keychain allows the rollover of authentication keys during the lifetime of a session.

Default

no auth-keychain

Parameters

name

Specifies the name of an existing keychain, up to 32 characters, to use for the specified TCP session or sessions.

backup-path

Syntax

[no] backup-path [ipv4] [ipv6]

Context

config>service>vprn>bgp

Platforms

7210 SAS-T, 7210 SAS-Sx/S 1/10GE (standalone and standalone-VC), 7210 SAS-Sx 10/100GE, and 7210 SAS-Mxp.

Description

This command enables the computation and use of a backup path for IPv4 and/or IPv6 BGP-learned prefixes belonging to the base router or a particular VPRN. Multiple paths must be received for a prefix to take advantage of this feature. When a prefix has a backup path and its primary paths fail the affected traffic is rapidly diverted to the backup path without waiting for control plane re-convergence to occur. When many prefixes share the same primary paths, and in some cases also the same backup path, the time to failover traffic to the backup path is independent of the number of prefixes.

By default, IPv4 and IPv6 prefixes do not have a backup path installed in the IOM.

Default

no backup-path

Parameters

ipv4

Enables the use of a backup path for BGP-learned unlabeled IPv4 prefixes.

ipv6

Enables the use of a backup path for BGP-learned unlabeled IPv6 prefixes.

connect-retry

Syntax

connect-retry seconds

no connect-retry

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the BGP connect retry timer value in seconds.

When this timer expires, BGP tries to reconnect to the configured peer. This configuration parameter can be set at three levels: global level (applies to all peers), peer-group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of this command used at the global level reverts to the default value.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

120

Parameters

seconds

The BGP Connect Retry timer value, in seconds, expressed as a decimal integer.

Values

1 to 65535

damping

Syntax

[no] damping

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables BGP route damping for learned routes which are defined within the route policy. Use damping to reduce the number of update messages sent between BGP peers and reduce the load on peers without affecting the route convergence time for stable routes. Damping parameters are set via route policy definition.

The no form of this command used at the global level disables route damping.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

When damping is enabled and the route policy does not specify a damping profile, the default damping profile is used. This profile is always present and consists of the following parameters:

Half-life:

15 minutes

Max-suppress:

60 minutes

Suppress-threshold:

3000

Reuse-threshold

750

Default

no damping

disable-4byte-asn

Syntax

[no] disable-4byte-asn

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command disables the use of 4-byte AS numbers. It can be configured at all 3 level of the hierarchy so it can be specified down to the per peer basis.

If this command is enabled 4-byte AS number support should not be negotiated with the associated remote peers.

The no form of this command resets the behavior to the default which is to enable the use of 4-byte AS number.

disable-capability-negotiation

Syntax

[no] disable-capability-negotiation

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command disables the exchange of capabilities. When this command is enabled and after the peering is flapped, any new capabilities are not negotiated and strictly support IPv4 routing exchanges with that peer.

The no form of this command removes this command from the configuration and restores the normal behavior.

Default

no disable-capability-negotiation

disable-capability-negotiation

Syntax

[no] disable-capability-negotiation

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command disables the exchange of capabilities. When command is enabled and after the peering is flapped, any new capabilities are not negotiated and strictly support IPv4 routing exchanges with that peer.

The no form of this command removes this command from the configuration and restores the normal behavior.

Default

no disable-capability-negotiation

disable-communities

Syntax

disable-communities [standard] [extended]

no disable-communities

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures BGP to disable sending communities.

Parameters

standard

Specifies standard communities that existed before VPRNs or 2547.

extended

Specifies BGP communities used were expanded after the concept of 2547 was introduced, to include handling the VRF target.

disable-fast-external-failover

Syntax

[no] disable-fast-external-failover

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures BGP fast external failover.

enable-peer-tracking

Syntax

[no] enable-peer-tracking

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables BGP peer tracking.

Default

no enable-peer-tracking

export

Syntax

export policy [policy...]

no export

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command specifies the export policies to be used to control routes advertised to BGP neighbors.

When multiple policy names are specified, the policies are evaluated in the order they are specified. A maximum of five (5) policy names can be configured. The first policy that matches is applied.

Note that if a non-existent route policy is applied to a VPRN instance, the CLI generates a warning message. This message is only generated at an interactive CLI session and the route policy association is made. No warning message is generated when a non-existent route policy is applied to a VPRN instance in a configuration file or when SNMP is used.

The no form of this command removes all route policy names from the export list.

Default

no export

Parameters

policy

Specifies a route policy statement name.

family

Syntax

family [ipv4] [ipv6]

no family

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the IP family capability.

The no form of this command reverts to the default.

Default

no family

Parameters

ipv4

Specifies IPv4 support.

ipv6

Specifies IPv6 support.

group

Syntax

group name [dynamic-peer]

no group

Context

config>service>vprn>bgp

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures a BGP peer group.

The no form of this command deletes the specified peer group and all configurations associated with the peer group. The group must be shutdown before it can be deleted.

Parameters

name

Specifies the peer group name. Allowed values is a string up to 32 characters composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.

dynamic-peer

Specifies that the specific BGP group is used by BGP peers created dynamically based on subscriber-hosts pointing to corresponding BGP peering policy. There can be only one BGP group with this flag set in any specific VPRN. No BGP neighbors can be manually configured in a BGP group with this flag set.

Default

disabled

neighbor

Syntax

[no] neighbor ip-address

Context

config>service>vprn>bgp>group

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command creates a BGP peer/neighbor instance within the context of the BGP group.

This command can be issued repeatedly to create multiple peers and their associated configuration.

The no form of this command removes the specified neighbor and the entire configuration associated with the neighbor. The neighbor must be administratively shutdown before attempting to delete it. If the neighbor is not shutdown, the command does not result in any action except a warning message on the console indicating that neighbor is still administratively up.

Parameters

ip-address

Specifies the IP address of the BGP peer router in dotted decimal notation.

Values

ipv4-address : a.b.c.d

family

Syntax

family [ipv4] [ipv6]

no family

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command specifies the address family or families to be supported over BGP peerings in the base router. This command is additive so issuing the family command adds the specified address family to the list.

The no form of this command removes the specified address family from the associated BGP peerings. If an address family is not specified, reset the supported address family back to the default.

Default

ipv4

Parameters

ipv4

Specifies support for IPv4 routing information.

ipv6

Specifies support for IPv6 routing information.

hold-time

Syntax

hold-time seconds [strict]

no hold-time

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the BGP hold time, expressed in seconds.

The BGP hold time specifies the maximum time BGP waits between successive messages (either keepalive or update) from its peer, before closing the connection. This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

Even though the router OS implementation allows setting the keepalive time separately, the configured keepalive timer is overridden by the hold-time value under the following circumstances:

  1. If the specified hold-time is less than the configured keepalive time, the operational keepalive time is set to a third of the hold-time; the configured keepalive time is not changed.

  2. If the hold-time is set to zero, the operational value of the keepalive time is set to zero; the configured keepalive time is not changed. This means that the connection with the peer is up permanently and no keepalive packets are sent to the peer.

The no form of this command used at the global level reverts to the default value.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

90

Parameters

seconds

The hold-time, in seconds, expressed as a decimal integer. A value of 0 indicates the connection to the peer is up permanently.

Values

0, 3 to 65535

strict

Specifies the advertised BGP hold-time from the far-end BGP peer must be greater than or equal to the specified value.

import

Syntax

import policy [policy...]

no import

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command specifies the import policies to be used to control routes advertised to BGP neighbors. Route policies are configured in the config>router>policy-options context. When multiple policy names are specified, the policies are evaluated in the order they are specified. A maximum of five (5) policy names can be specified. The first policy that matches is applied.

The no form of this command removes all route policy names from the import list.

Default

no import

Parameters

policy

Specifies aroute policy statement name.

keepalive

Syntax

keepalive seconds

no keepalive

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the BGP keepalive timer. A keepalive message is sent every time this timer expires. The seconds parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The keepalive value is generally one-third of the hold-time interval. Even though the OS implementation allows the keepalive value and the hold-time interval to be independently set, under the following circumstances, the configured keepalive value is overridden by the hold-time value:

If the specified keepalive value is greater than the configured hold-time, the specified value is ignored, and the keepalive is set to one third of the current hold-time value.

If the specified hold-time interval is less than the configured keepalive value, the keepalive value is reset to one third of the specified hold-time interval.

If the hold-time interval is set to zero, the configured value of the keepalive value is ignored. This means that the connection with the peer is up permanently and no keepalive packets are sent to the peer.

The no form of this command used at the global level reverts to the default value.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

30

Parameters

seconds

The keepalive timer, in seconds, expressed as a decimal integer.

Values

0 to 21845

local-address

Syntax

local-address ip-address

no local-address

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

Configures the local IP address used by the group or neighbor when communicating with BGP peers.

Outgoing connections use the local-address as the source of the TCP connection when initiating connections with a peer.

When a local address is not specified, the 7210 SAS uses the system IP address when communicating with iBGP peers and uses the interface address for directly connected eBGP peers. This command is used at the neighbor level to revert to the value defined under the group level.

The no form of this command removes the configured local-address for BGP.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Parameters

no local-address

Specifies the router ID is used when communicating with iBGP peers and the interface address is used for directly connected eBGP peers.

ip-address

Specifies the local address expressed in dotted decimal notation. Allowed values are a valid routable IP address on the router, either an interface or system IP address.

local-as

Syntax

local-as as-number [private]

no local-as

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures a BGP virtual autonomous system (AS) number.

In addition to the AS number configured for BGP in the config>router>autonomous-system context, a virtual (local) AS number is configured.The virtual AS number is added to the as-path message before the router AS number makes the virtual AS the second AS in the as-path.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). Therefore, by specifying this at each neighbor level, it is possible to have a separate as-number per eBGP session.

When a command is entered multiple times for the same AS, the last command entered is used in the configuration. The private attribute can be added or removed dynamically by reissuing the command.

Changing the local AS at the global level in an active BGP instance causes the BGP instance to restart with the new local AS number. Changing the local AS at the global level in an active BGP instance causes BGP to reestablish the peer relationships with all peers in the group with the new local AS number. Changing the local AS at the neighbor level in an active BGP instance causes BGP to reestablish the peer relationship with the new local AS number.

This is an optional command and can be used in the following circumstance:

Provider router P is moved from AS1 to AS2. The customer router that is connected to P, however, is configured to belong to AS1. To avoid reconfiguring the customer router, the local-as value on router P can be set to AS1. Therefore, router P adds AS1 to the as-path message for routes it advertises to the customer router.

The no form of this command used at the global level removes any virtual AS number configured.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

no local-as

Parameters

as-number

Specifies the virtual autonomous system number, expressed as a decimal integer.

Values

1 to 65535

private

Specifies the local-as is hidden in paths learned from the peering.

local-preference

Syntax

local-preference local-preference

no local-preference

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command sets the BGP local-preference attribute in incoming routes if not specified and configures the default value for the attribute. This value is used if the BGP route arrives from a BGP peer without the local-preference integer set.

The specified value can be overridden by any value set via a route policy. This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of this command at the global level specifies that incoming routes with local-preference set are not overridden and routes arriving without local-preference set are interpreted as if the route had local-preference value of 100.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

The default of no-local-preference does not override the local-preference value set in arriving routes and analyze routes without local preference with value of 100.

Default

no local-preference

Parameters

local-preference

Specifies the local preference value to be used as the override value, expressed as a decimal integer.

Values

0 to 4294967295

loop-detect

Syntax

loop-detect {drop-peer | discard-route | ignore-loop | off}

no loop-detect

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures how the BGP peer session handles loop detection in the AS path.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

Note that dynamic configuration changes of loop-detect are not recognized.

The no form of this command used at the global level reverts to default, which is loop-detect ignore-loop.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

loop-detect ignore-loop

Parameters

drop-peer

Sends a notification to the remote peer and drops the session.

discard-route

Discards routes received with loops in the AS path.

ignore-loop

Ignores routes with loops in the AS path but maintains peering.

off

Disables loop detection.

med-out

Syntax

med-out {number | igp-cost}

no med-out

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables advertising the Multi-Exit Discriminator (MED) and assigns the value used for the path attribute for the MED advertised to BGP peers if the MED is not already set.

The specified value can be overridden by any value set via a route policy.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of this command used at the global level reverts to default where the MED is not advertised.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

no med-out

Parameters

number

Specifies the MED path attribute value, expressed as a decimal integer.

Values

0 to 4294967295

igp-cost

Specifies the MED is set to the IGP cost of the specific IP prefix.

min-as-origination

Syntax

min-as-origination seconds

no min-as-origination

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the minimum interval, in seconds, at which a path attribute, originated by the local router, can be advertised to a peer.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of this command used at the global level reverts to default.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

15

Parameters

seconds

Specifies the minimum path attribute advertising interval, in seconds, expressed as a decimal integer.

Values

2 to 255

min-route-advertisement

Syntax

min-route-advertisement seconds

no min-route-advertisement

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the minimum interval, in seconds, at which a prefix can be advertised to a peer.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of this command reverts to default values.

Default

30

Parameters

seconds

The minimum route advertising interval, in seconds, expressed as a decimal integer.

Values

1 to 255

multihop

Syntax

multihop ttl-value

no multihop

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the Time To Live (TTL) value entered in the IP header of packets sent to an eBGP peer multiple hops away.

This parameter is meaningful only when configuring eBGP peers. It is ignored if set for an iBGP peer.

The no form of this command is used to convey to the BGP instance that the eBGP peers are directly connected.

The no form of this command reverts to default values.

Default

1 — eBGP peers are directly connected.

64 — iBGP

Parameters

ttl-value

Specifies the TTL value, expressed as a decimal integer.

Values

1 to 255

next-hop-self

Syntax

[no] next-hop-self

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the group or neighbor to always set the NEXTHOP path attribute to its own physical interface when advertising to a peer.

This is primarily used to avoid third-party route advertisements when connected to a multi-access network.

The no form of this command used at the group level allows third-party route advertisements in a multi-access network.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

The default means that third-party route advertisements are allowed.

Default

no next-hop-self

peer-as

Syntax

peer-as as-number

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the autonomous system number for the remote peer. The peer AS number must be configured for each configured peer.

For eBGP peers, the peer AS number configured must be different from the autonomous system number configured for this router under the global level, because the peer is in a different autonomous system than this router.

For iBGP peers, the peer AS number must be the same as the autonomous system number of this router configured under the global level.

This is a required command for each configured peer. This may be configured under the group level for all neighbors in a particular group.

Default

No AS numbers are defined.

Parameters

as-number

The autonomous system number, expressed as a decimal integer.

Values

1 to 65535

preference

Syntax

[no] preference preference

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the route preference for routes learned from the configured peers.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in peer-group) or neighbor level (only applies to specified peer). The most specific value is used.

The lower the preference the higher the chance of the route being the active route. The OS assigns BGP routes highest default preference compared to routes that are direct, static or learned via MPLS or OSPF.

The no form of this command used at the global level reverts to default value.

The no form of this command used at the group level reverts to the value defined at the global level.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

170

Parameters

preference

Specifies the route preference, expressed as a decimal integer.

Values

1 to 255

path-mtu-discovery

Syntax

[no] path-mtu-discovery

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command enables path MTU discovery for the associated TCP connections. In doing so, the MTU for the associated TCP session is initially set to the egress interface MTU. The DF bit is also set so that if a router along the path of the TCP connection cannot handle a packet of a particular size without fragmenting, it sends back an ICMP message to set the path MTU for the specific session to a lower value that can be forwarded without fragmenting.

The no form of this command disables path MTU discovery.

Default

no path-mtu-discovery

prefix-limit

Syntax

prefix-limit limit [log-only] [threshold percent]

no prefix-limit

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures the maximum number of routes BGP can learn from a peer.

When the number of routes reaches a certain percentage (default is 90% of this limit), an SNMP trap is sent. When the limit is exceeded, the BGP peering is dropped and disabled.

The no form of this command removes the prefix-limit.

Default

no prefix-limit

Parameters

limit

Specifies the number of routes that can be learned from a peer, expressed as a decimal integer.

Values

1 to 4294967295

log-only

Enables the warning message to be sent at the specified threshold percentage, and also when the limit is exceeded. However, the BGP peering is not dropped.

percent

Specifies the threshold value (as a percentage) that triggers a warning message to be sent. The default value is 90%.

rapid-withdrawal

Syntax

[no] rapid-withdrawal

Context

config>service>vprn>bgp

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command disables the delay (Minimum Route Advertisement) on sending BGP withdrawals. Normal route withdrawals may be delayed up to the minimum route advertisement to allow for efficient packing of BGP updates.

The no form of this command removes this command from the configuration and returns withdrawal processing to the normal behavior.

Default

no rapid-withdrawal

remove-private

Syntax

[no] remove-private

Context

config>service>vprn>bgp

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command allows private AS numbers to be removed from the AS path before advertising them to BGP peers.

When the remove-private parameter is set at the global level, it applies to all peers regardless of group or neighbor configuration. When the parameter is set at the group level, it applies to all peers in the group regardless of the neighbor configuration.

The software recognizes the set of AS numbers that are defined by IANA as private. These are AS numbers in the range 64512 through 65535, inclusive.

The no form of this command used at the global level reverts to default value.

The no form of this command used at the group level reverts to the value defined at the global level. The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

no remove-private — Private AS numbers are included in the AS path attribute.

type

Syntax

[no] type {internal | external}

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command designates the BGP peer as type internal or external.

The type of internal indicates the peer is an iBGP peer while the type of external indicates that the peer is an eBGP peer.

By default, the software derives the type of neighbor based on the local AS specified. If the local AS specified is the same as the AS of the router, the peer is considered internal. If the local AS is different, the peer is considered external.

The no form of this command used at the group level reverts to the default value.

The no form of this command used at the neighbor level reverts to the value defined at the group level.

Default

no type — Type of neighbor is derived on the local AS specified.

Parameters

internal

Configures the peer as internal.

external

Configures the peer as external.

ttl-security

Syntax

ttl-security min-ttl-value

no ttl-security

Context

config>service>vprn>bgp>group

config>service>vprn>bgp>group>neighbor

Platforms

Supported on all 7210 SAS platforms as described in this document, except those operating in access-uplink mode

Description

This command configures TTL security parameters for incoming packets.

Parameters

min-ttl-value

Specifies the minimum TTL value for an incoming BGP packet.

Values

1 to 255

Default

1