This command creates a text description stored in the configuration file for a configuration context.
The description command associates a text string with a configuration context to help identify the content in the configuration file.
The no form of this command removes the string from the configuration.
No description associated with the configuration context.
This command administratively disables an entity. When disabled, an entity does not change, reset, or remove any configuration settings or statistics.
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 may be deleted.
The no form of this command places the entity into an administratively enabled state.
This command enables tunnel selection algorithm based on the tunnel preference level.
The no form of the command reverts to the default.
next-preference-level
In case that a new session setup request is received while all tunnels on the same preference level are blacklisted, the L2TP session will try to be established on blacklisted tunnels before the tunnel selection moves to the next preference level.
This command will replace CDN Result-Code 4, 5 and 6 on LNS with the Result Code 2. This is needed for interoperability with some implementation of LAC which only take action based on CDN Result-Code 2, while ignore CDN Result-Code 4, 5 and 6.
The no form of the command reverts to the default.
no replace-result-code
By default, the LAC df-bit-lac is always set and sends all L2TP packets with the DF bit set to 1. The DF bit is configurable to allow downstream routers to fragment the L2TP packets. The LAC itself will not fragment L2TP packets. L2TP packets that have a larger MTU size than what the LAC egress ports allows are dropped.
The no form of the command reverts to the default.
df-bit-lac always
By default, the LAC df-bit-lac is set to default and sends all L2TP packets with the DF bit set to 1. The DF bit is configurable to allow downstream routers to fragment the L2TP packets. The LAC itself will not fragment L2TP packets. L2TP packets that have a larger MTU size than what the LAC egress ports allows are dropped. The configuration of the df-bit can be overridden at different levels: l2tp, tunnel, and group. The configuration at the tunnel level overrides the configuration on both the group and l2tp levels. The configuration at the group level overrides the configuration on l2tp.
The no form of the command reverts to the default.
df-bit-lac default
This command specifies the L2TP AVPs that should be ignored in L2TP session control.
The no form of the command reverts to the default.
no ignore-avps
This command configures an L2TP tunnel group.
The no form of the command reverts to the default.
none
This command configures an L2TP tunnel. A tunnel exists between a LAC-LNS pair and consists of a Control Connection and zero or more L2TP sessions. The tunnel carries encapsulated PPP datagrams and control messages between the LAC and the L2TP Network Server (LNS).
The no form of the command removes the tunnel name from the configuration.
none
This command enables the context to configure L2TP Tunnel Selection Blacklist parameters.
This command will force the tunnel to the blacklist and render it unavailable for new sessions for the duration of pre-configured time. Peers are always forced to the blacklist in case that they time out (failure to receive response to control packets). In addition to time outs, certain events can be used to trigger placement of the tunnel on the blacklist.
The no form of the command reverts to the default.
never
(4) Requestor is not authorized to establish a control channel
(5) Protocol version not supported
(6) Requestor is being shutdown or, in the case that the StopCCN with the following result codes is transmitted:
(4) Requestor is not authorized to establish a control channel.
(5) Protocol version not supported The receipt of the following Result Codes will never blacklist a tunnel:
(0) Reserved
(3) Control channel already exist
(7) Finite state machine error
(8) Undefined
Transmission of the following Result Codes will never blacklist a tunnel:
(1) General request to clear control connection
(3) Control channel already exist
(6) Requestor is being shutdown
(7) Finite state machine error
addr-change-timeout — A timed-out tunnel for which the peer IP address has changed mid-session (from the one that is provided initially during configuration) will be forced to the blacklist. In absence of this configuration option, only the configured peer for the tunnel will be blacklisted, but not the tunnel itself which now has a different peer address than the one initially configured.
This command configured the maximum length of the peer/tunnel blacklist.
This command specifies how many items (tunnels or peers) can be in the tunnel-selection-blacklist. If a tunnel or peer needs to be added to the tunnel-selection-blacklist and the tunnel-selection-blacklist is full, the system will remove the item (tunnel or peer) from the blacklist that was in this blacklist for the longest time.
The no form of the command reverts to the default.
unlimited
This command configures time for which an entity (peer or a tunnel) are kept in the blacklist.
The no form of the command reverts to the default.
5
This command defines an action that will be executed on the entity (peer/tunnel) in the blacklist once the entity becomes eligible for selection again.
The no form of the command reverts to the default.
remove-from-blacklist
This command sets the tunnel-id range that will be used to allocate a new tunnel-id for a tunnel for which no multi-chassis redundancy is configured.
non-multi-chassis-tunnel-id-range default or non-multi-chassis-tunnel-id-range start 1 end <maximum tunnel-id>
The default for start l2tp-tunnel-id is 1. No tunnel-ids are available for which no multi-chassis redundancy is configured when set to 0.
The default for end l2tp-tunnel-id is the maximum tunnel-id allowed on this system. The end l2tp-tunnel-id must be set to 0 when the start l2tp-tunnel-id is set to 0 and vice versa.
This command enables the context to configure tracked SRRP instances.
This command configures a tracked SRRP instance.
The no form of the command removes the SRRP instance identifier from the configuration.
This command sets the tunnel-id range that will be used to allocate a new tunnel-id for a tunnel for which multi-chassis redundancy is configured to this MCS peer.
The no form of the command reverts to the default.
Makes the tunnel ID empty.
This command configures the sub-set of sessions that this system attempts to synchronize in the Session State Synchronization phase as described in RFC 4951, Fail Over Extensions for Layer 2 Tunneling Protocol (L2TP).
The no form of the command reverts to the default.
2
This command sets the recovery method to be used for newly created tunnels.
The no form of the command reverts to the default.
mcs on config>router>l2tp>failover and config>service>vprn>l2tp>failover
default on config>router>l2tp>group>failover
default on config>router>l2tp>group>tunnel>failover
default on config>service>vprn>l2tp>group>failover
default on config>service>vprn>l2tp>group>tunnel>failover
![]() | Note: While failover is enabled, the tunnels and sessions proper are always kept synchronized between the redundant pair, regardless of the recovery method for the sequence numbers when a failover really occurs. |
This command sets the recovery time to be negotiated via RFC 4951. It represents the extra time this L2TP peer (LAC or LNS) needs to recover all its tunnels.
The no form of the command reverts to the default.
0 on config>router>l2tp>failover and config>service>vprn>l2tp>failover
This command sets the sync-tag to be used to synchronize the tunnels with track-srrp srrp-id to MCS peer IP-@. The same sync-tag should be configured on the MCS peer.
The no form of the command reverts to the default.
Removes the sync-tag for the indicated track-srrp.
This command configures an L2TP tunnel.
The no form of the command removes the tunnel name from the group configuration.
no access
router-instance: | |
router-name: | “Base” |
vprn-svc-id: |
This command creates a text description stored in the configuration file for a configuration context.
The description command associates a text string with a configuration context to help identify the content in the configuration file.
The no form of this command removes the string from the configuration.
No description associated with the configuration context.
no network
router-instance: | |
router-name: | “Base” |
vprn-svc-id: |
This command enables the L2TP accounting.
The no form of this command disables accounting.
none
This command specifies the accounting type for the L2TP tunnel accounting policy.
The no form of the command reverts to the default.
session tunnel
Tunnel-Link-Start
Tunnel-Link-Stop
Tunnel-Link-Reject
Tunnel-Start
Tunnel-Stop
Tunnel-Reject
This command enables the context to specify the RADIUS parameters that the system should include into RADIUS authentication-request messages.
The no form of the command disables the RADIUS attributes to be included in the policy.
This command enables the generation of the nas-identifier RADIUS attribute.
The no form of the command reverts to the default.
no nas-identifier
This command enables the generation of the nas-port RADIUS attribute. You enter decimal representation of a 32-bit string that indicates your port information. This 32-bit string can be compiled based on different information from the port (data types). By using syntax number-of-bits data-type you indicate how many bits from the 32 bits are used for the specific data type. These data types can be combined up to 32 bits in total. In between the different data types 0's and/or 1's as bits can be added.
The no form of this command disables the nas-port configuration.
binary-spec | <bit-specification> <binary-spec> | |
bit-specification | 0 | 1 | <bit-origin> | |
bit-origin | *<number-of-bits><origin> | |
number-of-bits | 1 to 32 | |
origin | o | i | s | m | p | |
outer VLAN ID | ||
i | inner VLAN ID | |
s | slot number | |
m | MDA number | |
p | port number or lag-id |
The following output shows an example.
This command enables the generation of the nas-port-id RADIUS attribute. Optionally, the value of this attribute (the SAP-id) can be prefixed by a fixed string and suffixed by the circuit-id or the remote-id of the client connection. If a suffix is configured, but no corresponding data is available, the suffix used will be 0/0/0/0/0/0.
The no form of the command reverts to the default.
no nas-port-id
This command enables the generation of the nas-port-type RADIUS attribute. If set to nas-port-type, the following will be sent: values: 32 (null-encap), 33 (dot1q), 34 (qinq), 15 (DHCP hosts). The nas-port-type can also be set as a specified value, with an integer from 0 to 255.
The no form of the command reverts to the default.
no nas-port-type
This command enables the context for defining RADIUS accounting server attributes under a given session authentication policy.
This command configures the algorithm used to access the list of configured RADIUS servers.
The no form of the command reverts to the default.
direct
This command configures the number of times the router attempts to contact the RADIUS server for authentication.
![]() | Note: The retry count includes the first attempt. |
The no form of the command reverts to the default value.
3 (the initial attempt as well as two retried attempts)
This command specifies the number of times the router attempts to contact the RADIUS server for authentication, if not successful the first time.
The no form of the command reverts to the default value.
no router
router-name | vprn-svc-id | |
router-name | Base, management Default - Base |
vprn-svc-id | 1 to 2147483647 |
This command adds a RADIUS server and configures the RADIUS server IP address, index, and key values.
Up to five RADIUS servers can be configured at any one time. RADIUS servers are accessed in order from lowest to highest index for authentication requests until a response from a server is received. A higher indexed server is only queried if no response is received from a lower indexed server (which implies that the server is not available). If a response from a server is received, no other RADIUS servers are queried.
The no form of the command removes the server from the configuration.
none
This command configures the source address of the RADIUS messages.
The no form of the command reverts to the default value.
system IP address
This command configures the number of seconds the router waits for a response from a RADIUS server.
The no form of the command reverts to the default value.
5
This command specifies the RADIUS script policy to be used for accounting-request packets.
The no form of the command removes the policy from the configuration.
![]() | Note: The command outputs in the following section are examples only; actual displays may differ depending on supported functionality and user configuration. |
This command displays L2TP peer operational information/
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 to FFFF]H | |
d - [0 to 255]D | |
draining | keyword |
statistics | keyword |
port | [1 to 65535] |
The following output is an example of L2TP peer information.
This command displays L2TP system information.
The following output is an example of L2TP system information.
This command displays synchronization information.
The following output is an example of multi-chassis sync information.
This command enables and configures debugging for the L2TP tunnel with a given assignment-id
This command configures an L2TP debugging event.
This command enables and configures debugging for an L2TP group.
This command enables and configures debugging for an L2TP peer.
This command enables and configures debugging for an L2TP tunnel.
This command configures L2TP LAC state recovery event debugging.
This command configures L2TP LAC state recovery failed event debugging.