Our project was to change a branch network from a common OSPF area (area 2) to branch specific areas. We made all of the necessary head end changes on our ASR platform and then to the primary 3945 WAN router at the first branch. We successfully established OSPF adjacencies across the WAN on the new OSPF area (area 4). However, when we attempted to make the changes on the next branch device, a 3750X-48PS, layer 3 access switch, we were unable to establish any adjacencies with the 3945 WAN device. We cleared the OSPF process but this did not fix the problem. This is the output from the "sh ip ospf database sum" on the access switch:
OSPF Router with id (169.x.x.x) (Process ID XXXXX)
Router Link States (area 0.0.0.2)
Link ID Adv Router Age Seq # Checksum Link Count
169.x.x.x 169.x.x.x 2833 0X80001A9B 0X00615D 6
169.x.x.x 169.x.x.x 540 0X80001A7A 0X00A748 5
Router Link States (area 4)
169.x.x.x 169.x.x.x 1407 0X80000003 0X002D12 2
A "sh log | inc OSPF" output showed the OSPF area changing to 4 but the adjacency was never formed across the new area. The only way to clear the original area (2) from the database was to reload the layer 3 access switch.
Has anyone come across a similar issue while migrating to a new OSPF area?
