Distribute List

• OSPF routes can't be filtered from entering the OSPF database.
  • The DISTRIBUTE-LIST IN command only filters routes from entering the routing table, but it doesn't prevent link-state packets from being propagated.
• The command distribute-list out works only on the routes being redistributed by the autonomous system boundary routers (ASBRs) into OSPF.
  • It can be applied to external type 2 and external type 1 routes, but not to intra-area and inter-area routes.

Distribute-list in/out:

• Distribute-list in: Do not use if the protocol is already distributed into receiving protocol
• Distribute-list out: Can be used either on protocol or on interface. It controls what routes are redistributed into the receiving protocol.