ospf filter-lsa-out
Function
The ospf filter-lsa-out command configures the specified interface enabled with OSPF to filter outgoing LSAs.
The undo ospf filter-lsa-out command configures a router not to filter outgoing LSAs.
By default, outgoing LSAs are not filtered.
Format
ospf filter-lsa-out { all | { summary [ acl acl-number ] | ase [ acl acl-number ] | nssa [ acl acl-number ] } * }
undo ospf filter-lsa-out
Parameters
| Parameter | Description | Value |
|---|---|---|
| all | Filters all outgoing LSAs except grace LSAs. | - |
| summary | Filters outgoing network summary LSAs (Type-3). | - |
| ase | Filters outgoing AS external LSAs (Type-5). | - |
| nssa | Filters outgoing NSSA LSAs (Type-7). | - |
| acl acl-number | Specifies the number of the basic ACL. | The value is an integer that ranges from 2000 to 2999. |
Views
Ethernet interface view, Ethernet sub-interface view, Eth-Trunk interface view, Eth-Trunk sub-interface view, Tunnel interface view, Dialer interface view, VLANIF interface view, Virtual-Template interface view, BDIF interface view
Usage Guidelines
Usage Scenario
When multiple links exist between two routers, based on the filtering policy, the ospf filter-lsa-out command configures the local router to filter the outgoing LSAs before sending them along specified links. This can reduce the unnecessary retransmission of LSAs and save bandwidth resources.
Configuration Impact
Filtering the outgoing LSAs on the specified OSPF interface can prevent useless LSAs from being sent to neighbors. This can reduce the size of the LSDB of neighbors and speed up the network convergence.
After the command is configured on an interface, the OSPF neighbor relationship of the interface will automatically re-establish.
Precautions
Grace LSAs are used to inform the neighbor of the Graceful Restart (GR) time, cause, and interface instance ID when GR starts and ends. The command is not used to filter the grace LSAs.