Enabling LDP GR

This section describes how to configure LDP GR on both the GR Restarter and its neighbor nodes.

Context

You can enable LDP GR to maintain proper forwarding and resume the LDP session and establish LSPs after a switchover or system update is performed.

In practical applications, system-level GR is usually configured in the hardware environment with dual main control boards. System-level GR allows the system to forward services if the main control board fails.

Perform the following steps on the LDP GR Restarter and its neighbor nodes:

Procedure

Access the system view.
```
system-view
```
Configure ae local LSR ID.
```
mpls lsr-id lsr-id
```
Enable the MPLS function on the local node and access the MPLS view.
```
mpls
```
Return to the system view.
```
quit
```
Enable the LDP function on the local node and access the LDP view.
```
mpls ldp
```
Enable the GR function.
```
graceful-restart
```
By default, the LDP GR function is disabled.
- When the LDP GR is enabled or disabled, the LDP session is renewed.
- During the LDP GR process, the undo mpls ldp and reset mpls ldp commands are not permitted.
- During the LDP GR process, the modification of the LSP trigger policy using the lsp-trigger, propagate mapping or lsp-trigger bgp-label-route command is invalid.