Usage Scenario
In OSPF, intra-area links take precedence over inter-area links. Therefore, even if a high-speed link exists between two areas, a low-speed intra-network link rather than the high-speed link is used to transmit inter-area traffic. To address this problem, run the ospf enable multi-area command to enable OSPF on a multi-area adjacency interface so that a link can be shared by multiple areas.
Prerequisites
OSPF has been enabled on the interface using the ospf enable [ process-id ] area area-id command.
Precautions
If the ospf enable multi-area and ospf enable commands are run on the same interface, the areas specified in the commands must be different.
The
ospf enable multi-area command does not apply to OSPF DCN interfaces.
If OSPF has been enabled on an interface of a virtual link in a transit area using the ospf enable or
ospf enable multi-area command, OSPF cannot be enabled on the interface in the backbone area.