Adjusting the IPv6 IS-IS Route Convergence Speed

Accelerating IS-IS route convergence can improve the fault location efficiency and network reliability.

Usage Scenario

The procedure for implementing IS-IS is as follows:

Establishment of neighboring relationships: establishes neighboring relationships by exchanging Hello packets between two devices.
LSP flooding: implements LSDB synchronization between devices in the same area.
SPF calculation: uses the SPF algorithm to calculate IS-IS routes, and delivers the IS-IS routes to the routing table.

To accelerate the IS-IS route convergence, configure the following parameters:

Interval for detecting IS-IS neighboring device failures.
Flooding parameters of CSNPs and LSPs.
Interval for SPF calculation.

You can also configure convergence priorities for IPv6 IS-IS routes so that key routes can converge first if the network topology changes, which minimizes adverse impacts on key services.

Pre-configuration Tasks

Before configuring the IPv6 IS-IS route convergence speed, complete the following tasks:

Configure the link layer protocol on interfaces.
Configure IP addresses for interfaces to ensure that neighboring nodes are reachable at the network layer.
Configure basic IPv6 IS-IS functions.

Configuring the Interval for Detecting IS-IS Neighboring Device Failures: To minimize the effects caused by neighboring device failures on an IS-IS network, accelerate the speed of detecting IS-IS neighboring device failures.

Setting Flooding Parameters of SNPs and LSPs: To speed up LSDB synchronization between devices, set flooding parameters of SNPs and LSPs to proper values.

Setting the SPF Calculation Interval: To improve the fault location efficiency on an IS-IS network and prevent SPF calculation from consuming excessive system resources, set the SPF calculation interval to a proper value.

Configuring Convergence Priorities for IPv6 IS-IS Routes: If some IS-IS routes need to be converged by priority to minimize adverse impacts on services, configure those routes to have the highest convergence priority.

Configuring Interface Address Advertisement Suppression: Interface address advertisement suppression ensures that interface addresses can be reused.

Verifying the Configuration: After configuring parameters to adjust the IPv6 IS-IS route convergence speed, check the configurations.