If no level is specified, both Level-1 and Level-2 are configured.
For IS-IS, when the local routing information is changed, some new LSPs (or LSP fragments) need to be generated to advertise the change of routes. If the change occurs frequently, immediate generation of LSPs (or LSP fragments) and a large number of resources on the system will be occupied. On the other hand, a long delay of the LSPs (or LSP fragments) generation prevents the changes of local routing information from reaching neighbors in time. This slows down network convergence.


To speed up network convergence and prevent the system from being affected, use an intelligent timer for generating LSPs. The timer can adjust the delay time based on the change frequency of the routing information automatically.


The initial delay time for generating the LSPs is init-interval. The delay time for generating the LSPs with the same LSP ID the second time is incr-interval. Each time the routes change, the delay time for generating the LSPs with the same LSP ID is twice as the previous value until the delay time reaches max-interval. After the delay reaches max-interval for three times or the IS-IS process is reset, the delay time is reduced to init-interval.
When incr-interval is not used and the LSPs with the same LSP ID are generated for the first time, init-interval is used as the initial delay time. Then, the delay time for generating the LSPs with the same LSP ID is max-interval. After the delay time reaches max-interval for three times or the IS-IS process is reset, the delay time is reduced to init-interval.

When only max-interval is used, the intelligent timer becomes an one-short triggered timer.

Example:

Set the delay time for generating an LSP to 5 seconds.

[SAVAR_NE40E] isis
[SAVAR_NE40E-isis-1] timer lsp-generation 5

good detailed information. thanks

nice doc. thanks

nice info.thanks

useful document, thanks