timer spf

Use timer spf to set the SPF calculation interval.

Use undo timer spf to restore the default.

Syntax

timer spf maximum-interval [ minimum-interval [ incremental-interval ] ]

undo timer spf

Default

The maximum interval is 5 seconds, the minimum interval is 50 milliseconds, and the incremental interval is 200 milliseconds.

Views

IS-IS view

Predefined user roles

network-admin

Parameters

maximum-interval: Specifies the maximum SPF calculation interval in the range of 1 to 120 seconds.

minimum-interval: Specifies the minimum SPF calculation interval in the range of 10 to 60000 milliseconds.

incremental-interval: Specifies the incremental SPF calculation interval in the range of 10 to 60000 milliseconds.

Usage guidelines

Based on the LSDB, an IS-IS router uses the SPF algorithm to calculate a shortest path tree with itself being the root, and uses the shortest path tree to determine the next hop to a destination network. By adjusting the SPF calculation interval, you can prevent bandwidth and router resources from being overused due to frequent topology changes.

When network changes are not frequent, the minimum-interval is adopted. If network changes become frequent, the SPF calculation interval increases by the incremental-interval each time a generation happens until the maximum-interval is reached.

The minimum interval and the incremental interval cannot be greater than the maximum interval.

Examples

# Set the maximum interval to 10 seconds, the minimum interval to 100 milliseconds, and the incremental interval to 300 milliseconds, respectively.

<Sysname> system-view
[Sysname] isis 1
[Sysname-isis-1] timer spf 10 100 300