OSPF Route Filtering

Route filtering in OSPF allows administrators to control which routes are advertised or learned, helping to manage routing table size and enforce network policies.

Common Filtering Methods:

  • Distribute-list: Filters routes based on access-lists. Can be applied inbound or outbound.
  • Prefix-list: More flexible than access-lists for IP prefix matching.
  • Route-map: A powerful and versatile tool for complex filtering and manipulation of routes.

Example (Distribute-list):

access-list 10 deny 192.168.1.0 0.0.0.255
access-list 10 permit any
router ospf 1
 distribute-list 10 in GigabitEthernet0/0