Configuration rules

If the switch is to operate as an ASBR, you must enable redistribution (step 7 in General configuration steps for OSPF.

When you do that, ASBR capability is automatically enabled. For this reason, you should first configure redistribution filters on the ASBR. Otherwise, all possible external routes will be allowed to flood the domain. (See Configuring external route redistribution in an OSPF domain (optional).)

Each VLAN interface on which you want OSPF to run must be assigned to one of the defined areas. When a VLAN interface is assigned to an area, the IP address is automatically included in the assignment. To include additional addresses, you must enable OSPF on them separately, or use the "all" option in the assignment.