# Guidelines for Setting the IP Interface Priority

During the warm restart after an SRP switchover, IP and IPv6 interfaces are replayed from NVS and from mirrored storage. High-priority IP and IPv6 interfaces are replayed first, followed by static routes, and then by low-priority IP and IPv6 interfaces. This scheme enables static routes that are dependent on high-priority interfaces to be resolved and routing protocols to exchange information with peers over high-priority interfaces before the low-priority interfaces are replayed.

You can designate an IP or IPv6 interface as high priority either implicitly or explicitly:

- Implicit designation—Configure an IGP or PIM protocol on the interface.
- Explicit designation—Issue the ip initial-sequence-preference 1 command on the IP subinterface, or the ipv6 initial-sequence-preference 1 command on the IPv6 subinterface.

An IP or IPv6 interface can be designated as high priority by more than one protocol, the CLI command, or both. You can change an IP or IPv6 interface from high priority to low priority only by one of the following methods:

- Delete the IP or IPv6 interface.
- Remove all high-priority configuration from the IP or IPv6 interface, then reload the router.

#### Related Documentation

- Setting the IP Interface Priority
- ip initial-sequence-preference
- ipv6 initial-sequence-preference