Supported Platforms
AS PIC Redundancy for L2TP Services
L2TP services support AS PIC redundancy. To configure redundancy, you specify a redundancy services PIC (rsp) interface in which the primary AS PIC is active and a secondary AS PIC is on standby. If the primary AS PIC fails, the secondary PIC becomes active, and all service processing is transferred to it. If the primary AS PIC is restored, it remains in standby and does not preempt the secondary AS PIC; you need to manually restore the services to the primary PIC. To determine which PIC is currently active, issue the show interfaces redundancy command.
 | Note: On L2TP, the only service option supported is warm standby, in which one backup PIC supports multiple working PICs. Recovery times are not guaranteed, because the configuration must be completely restored on the backup PIC after a failure is detected. The tunnels and sessions are torn down upon switchover and need to be restarted by the LAC and PPP client, respectively. However, configuration is preserved and available on the new active PIC, although the protocol state needs to be reestablished. As with the other AS PIC services that support warm standby, you can issue the request interfaces (revert | switchover) command to manually switch between primary and secondary L2TP interfaces. |
For more information, see Configuring AS or Multiservices PIC Redundancy. For an example configuration, see Examples: Configuring L2TP Services. For information on operational mode commands, see the Junos OS Operational Mode Commands.
