The topology is according to scheme bellow:
After resetting the ospf process, the ospf peer can't be establish between (2) and (4) , but sometimes (4) and (1) establish ospf peering.
The ping between (2) and (4) pass without any problem
After checking the configuration we have found that the link (1)-(3) and (2)-(4) use vlan 131 for inteconnection and the link (1)-(2) and (3)-(4)
use vlan 132 for interconnexion, also all the ospf network type between each Switch is configurd to be p2p on Gigaethernet interfaces,and each segment has a different subnet
After that we have checked if we have a loop in our network,we have found that there is no loop but vlan 131 is enabled in the
physical interface between (1) and (2).
After that we have deleted the p2p configuration in all vlan interfaces and the problem has been solved.
The reason of this problem is that when we have configured the vlanif 131 between (2) and (4) as p2p,hello packets sent by (4) should be received just by (2), but in this case and
since hello packets are multicast(188.8.131.52) also (1) and (3) receive hello packets sent by (4) and the ospf peer can be estblished also between (4) and (1) or (4) and (3),
even they have different mask, because ospf when using p2p don't care about mask network.
To solve this problem it's better to disable vlan 131 between (1) and (2)
vlan miss much configuration
One other interesting feature of point-to-point (serial/WAN) links is that there can be unnumbered. Besides, each endpoint can have even a different IP subnet and each sender is identified by the Router ID (instead of physical interface address). This means that the subnet mask in hello packets doesn't need to be the same on both routers (this is not possible in a broadcast network).