Configuring a Pool of Inline Services Interfaces for Dynamic LNS Sessions
You can create a pool of inline service interfaces, also known as a service device pool, to enable load-balancing of L2TP traffic across the interfaces. The pool is supported for dynamic LNS configurations, where it provides a set of logical interfaces that can be dynamically created and allocated to L2TP sessions on the LNS. The pool is assigned to an LNS tunnel group. L2TP maintains the state of each inline service interface and uses a round-robin method to evenly distribute the load among available interfaces when new session requests are accepted.
 | Note: Load balancing is available only for dynamically created subscriber interfaces. |
LNS sessions anchored on an MPC are not affected by a MIC failure as long as some other path to the peer LACs exists. If the MPC hosting the peer interface fails and there is no path to peer LACs, the failure initiates termination and clean-up of all the sessions on the MPC.
If the MPC anchoring the LNS sessions itself fails, the Routing Engine does not relocate sessions to another slot and all sessions are terminated immediately. New sessions can come up on another available interface when the client retries.
To configure the service device pool:
- Create the pool.[edit services service-device-pools]user@host# edit pool pool-name
- Specify the inline service interfaces that make up the pool.
