outbound peer fec

Function

The outbound peer fec command configures an outbound policy for allowing Label Mapping messages carrying a specified Interior Gateway Protocol (IGP) route to be sent to a specified peer.

The undo outbound peer fec command restores the default configuration.

By default, no outbound policy is configured to allow Label Mapping messages carrying a specified IGP route to be sent to a specified peer.

Format

outbound peer { peer-id | peer-group peer-group-name | all } fec { none | host | ip-prefix prefix-name }

undo outbound peer { peer-id | peer-group peer-group-name | all } fec

Parameters

Parameter	Description	Value
peer-id	Specifies the ID of an LDP peer. By default, the peer ID is specified by the mpls lsr-id command. If the lsr-id command has been configured, the peer ID is specified by the lsr-id command.	-
peer-group peer-group-name	Specifies the name of a peer group. The parameter is specified by the ip ip-prefix command.	-
all	Indicates all LDP peers.	-
none	Prohibits Label Mapping messages carrying routes mapped to all Forwarding Equivalence Classes (FECs) from passing the policy. After the parameter none is configured, no Label Mapping messages carrying IGP routes mapped to all FECs are sent to a specified peer.	-
host	Allows Label Mapping messages carrying the host routes mapped to FECs to pass the policy. After the parameter host is configured, Label Mapping messages carrying host routes mapped to all FECs are sent to a specified peer.	-
ip-prefix prefix-name	Allows Label Mapping messages carrying IGP routes that are defined in the IP prefix list and mapped to FECs to pass the policy. After the parameter ip-prefix is configured, Label Mapping messages carrying IGP routes that are defined in the IP prefix list and mapped to FECs are sent to a specified peer. The parameter is specified by the ip ip-prefix command.	-

Views

MPLS-LDP view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

A label switching router (LSR) sends Label Mapping messages to both upstream and downstream LDP peers by default, speeding up LDP label switched paths (LSPs) convergence. This leads to a great number of unwanted LSPs to be established, wasting resources. To reduce the number of LSPs and save memory resources, configure an outbound or inbound policy to filter out LDP LSPs not matching the policy.

When running the outbound peer fec command, specify the peer ID and FEC of the IGP route, configuring the peer to receive only Label Mapping messages for specified IGP routes. This setting helps reduce the number of Label Mapping messages to be 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 peer-group-name or all parameter in the command.

Prerequisites

MPLS LDP has been enabled globally using the mpls ldp command in the system view.

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 peer-id 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 the LDP peer with peer-id of 2.2.2.2:

outbound peer 2.2.2.2 fec none

Creating a peer group before it is referenced is recommended. By default, nonexistent peer groups cannot be referenced using the command. If the route-policy nonexistent-config-check disable command is run in the system view and a nonexistent peer group is referenced using the current command, the current command applies to all LDP peers.

Creating an IP prefix list before it is referenced is recommended. By default, nonexistent IP prefix lists cannot be referenced using the command. If the route-policy nonexistent-config-check disable command is run in the system view and a nonexistent IP prefix list is referenced using the current command, the device advertises Label Mapping messages of all LDP FECs to the specified peer.

Example

# Configure an LSR to send Label Mapping messages carrying host routes to all peers.

<sysname> system-view
[sysname] mpls ldp
[sysname-mpls-ldp] outbound peer all fec host