Configuring prefix suppression

An OSPF interface by default advertises all its prefixes in LSAs. You can suppress interfaces from advertising all its prefixes to speed up OSPF convergence. This function also helps improve the network security by preventing IP routing toward the suppressed networks.

When prefix suppression is enabled:

• On P2P and P2MP networks, OSPF does not advertise Type-3 links in Router LSAs. Other routing information can still be advertised to ensure traffic forwarding.

• On broadcast and NBMA networks, the DR generates Network LSAs with a mask length of 32 to suppress network routes. Other routing information can still be advertised to ensure traffic forwarding. If no neighbors exist, the DR does not advertise the primary IP addresses of interfaces in Router LSAs.

	IMPORTANT: If you want to use prefix suppression, configure prefix suppression on all OSPF routers as a best practice.