This command is used by the OSPF to set the forwarding address for the redistributed type-5 LSAs. The value of the forwarding address specified by the autonomous system boundary router (ASBR) can be either 0.0.0.0 or nonzero. The 0.0.0.0 address indicates that the originating router (the ASBR) is the next hop.
If the ASBR redistributes routes and OSPF is not enabled on the next hop interface for those routes, the forwarding address is set to 0.0.0.0 .
All of the following conditions must be met to set the forwarding address field to a nonzero address:
OSPF is enabled on the ASBR's next hop interface.
ASBR’s next hop interface is non-passive under OSPF.
ASBR’s next hop interface is not point-to-point.
ASBR’s next hop interface is not point-to-multipoint.
For all other conditions, set the forwarding address to 0.0.0.0.