# Enabling Tunnel Switching

L2TP tunnel switching allows you to switch packets between one session terminating at an L2TP LNS and another session originating at an L2TP LAC. What distinguishes a tunnel-switched LAC from a conventional one is that there are two interface columns: one for the incoming session (LNS) and one for the outgoing session (LAC). The router forwards traffic from the incoming session to the outgoing session and vice versa.

You can select tunnel switching on a per-chassis basis. By default, tunnel switching is disabled. This preserves current behavior and prevents inadvertent attempts to switch tunnels.

| Note: Each individual L2TP session involved in tunnel switching is counted toward the maximum number of sessions supported on an E Series router.

- To enable tunnel switching:
  host1(config)#l2tp tunnel-switching

#### Related Documentation

- l2tp tunnel-switching