Usage Scenario
By default, an LSR sends Label Mapping messages to both upstream and downstream LDP peers to speed up the convergence of LDP LSPs. This results in the establishment of a large number of LSPs, wasting resources. An outbound policy can be configured to prevent LDP LSPs with routing information failing to pass the policy from being established. This policy helps reduce the number of LDP LSPs to be established and saving memory.
The
outbound peer fec command can be used to specify the peer ID and FEC (to which a specified route is mapped) to allow Label Mapping messages for specific routes to be sent to a specified peer. This setting prevents unwanted Label Mapping messages from being sent.
To apply a policy associated with a single FEC range to an LDP peer group or all LDP peers that send Label Mapping messages, configure either the peer-group or all parameter in the command.
Precautions
If multiple outbound policies are configured for a specified LDP peer, the first configured one takes effect. For example, the following two outbound policies are configured:
outbound peer 2.2.2.2 fec host
outbound peer peer-group group1 fec none
As group1 also contains an LDP peer with address of 2.2.2.2, the following outbound policy takes effect:
outbound peer 2.2.2.2 fec host
If two outbound policies are configured in sequence and the peer parameters in the two commands are the same, the second command overrides the first one. For example, the following two outbound policies are configured:
outbound peer 2.2.2.2 fec host
outbound peer 2.2.2.2 fec none
The second configuration overrides the first one. This means that the following outbound policy takes effect on an LDP peer with address of 2.2.2.2:
outbound peer 2.2.2.2 fec none
If outbound peer all fec { none | host | ip-prefix } is configured, it overrides all previous configured outbound policies for routes.
To delete all outbound policies in batches, run the
undo outbound peer all command.