The graceful-delete timer command sets the delay after which LDP instructs the upstream device to withdraw labels when an LDP session goes Down.
The undo graceful-delete timer command restores the default setting.
By default, LDP instructs the upstream device to withdraw labels 5 seconds after the LDP session goes Down.
| Parameter | Description | Value |
|---|---|---|
| timer | Specifies the delay after which LDP instructs the upstream device to withdraw labels when an LDP session goes Down. | An integer ranging from 1 to 65535, in seconds |
Usage Scenario
When an LDP session goes Down, the label switched path (LSP) together with the LDP session will be deleted, causing service interruption. After LDP graceful deletion is configured, LDP does not immediately instruct the upstream device to withdraw labels but keeps the LSP until the LDP session is restored, ensuring uninterrupted traffic and preventing LDP LSP flapping. This improves the network reliability. Run the graceful-delete timer command to set the value for the graceful deletion timer. Restoring the default value for the graceful deletion timer is recommended.
Prerequisites
LDP graceful deletion has been globally configured.
Follow-up Procedure
Run the display mpls ldp command to check whether the configuration is complete.
Precautions
Do not set a large value for the graceful deletion timer. If the value of the graceful deletion timer is too large, remaining the invalid LSP state consumes system resources.