A, B, C and D sub-sites use NE80. Four NE80s are connected through POS2.5G port and OSPF is enabled between devices. Four POS ports are configured in one area. A is near to B and C. The problem is as follows:
1. Ping address X.X.X.77 from A site NE80 PING. Sometimes it is time outs.(X.X.X.77 is IP address of B site NE80 connected with 8750 GE.)
A subsite routing information with X.X.X.77 as destination address on NE80 is learnt from direct rotue of B subsite through OSPF. Check routing table and sometimes there is no information of this route on NE80 of A subsite.
2. Different time segment collects routing information separately. Check routing table on NE80 of A subsite and twice capture result is different.
The next-hop of the route should point to NE80 of B subsite, but it points to NE80 of C subsite. Imported static route and direct route of NE80 of B subsite and NE80 of C subsite sometimes occurs on NE80 of A subsite. Parts of route is not stable.
Change NE80 of B and C subsites as non-confilct. The routing table does no longer flaps and PING X.X.X.77 is normal. The problem is solved.
1. Check configuration file captured twice by A, B, C and D and there is no difference. But there is a serious problem. OSPF Router id of NE80 of B subsite and NE80 of C subsite is conflicted.
2. Because of Router id conflict, NE80 of A subsite change routing information continuously, which learned updated routing information from B and C alternately, and routing table is flapping.