R3303-HP HSR6800 Routers MPLS Configuration Guide

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Configuring BFD for MPLS LDP
Use BFD to help MPLS promptly detect a neighbor failure or link failure between two remote LDP peers.
BFD can help MPLS LDP detect communication failures only between remote LDP peers. For configuration
examples, see "Configuring VPLS." For more information about BFD, see High Availability Configuration
Guide.
To configure BFD for MPLS LDP:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter MPLS LDP remote
peer view.
mpls ldp remote-peer
remote-peer-name
N/A
3. Enable BFD for MPLS LDP.
remote-ip bfd
By default, BFD is disabled for
MPLS LDP.
One LSP can have only one BFD
session.
Resetting LDP sessions
If you change LDP session parameters when some LDP sessions are up, the LDP sessions cannot function
correctly. In this case, reset LDP sessions so the LDP peers will renegotiate parameters and establish new
sessions.
To reset LDP sessions:
Task Command Remarks
Reset LDP sessions.
reset mpls ldp [ all | [ vpn-instance
vpn-instance-name ] [ fec mask |
peer peer-id ] ]
Available in user view.
Managing and optimizing MPLS forwarding
Perform the tasks in this section to manage and optimize MPLS forwarding for higher performance.
Configuring MPLS MTU
An MPLS label stack is inserted between the link layer header and the network layer header. During
MPLS forwarding, a packet, after encapsulated with an MPLS label, might exceed the allowed length of
the link layer and cannot be forwarded, although the network layer packet is smaller than the interface
MTU.
To address the issue, you can configure the MPLS MTU on an interface of an LSR. Then, the LSR compares
the length of an MPLS packet against the configured MPLS MTU on the interface. If the packet is larger
than the MPLS MTU: