Hello Nor
There’s no set way how to check that routing is being performed correctly on an overall OSPF topology. It may be necessary to check each individual router to ensure that routing is being performed as you desire.
This is an issue that must be faced with any large network that employs routing. How do you manage such a network with potentially hundreds of routers without having to inspect each individual router? Well, there are a couple of approaches, but all rely on a sound initial design plan.
For OSPF, creating a scalable network requires that you separate your network into individual areas that can be more easily managed. You also must have a policy as far as how routes will be shared between areas employing summarization as needed. Some general principles to follow can be found in this Cisco documentation:
Now having said that, you can also monitor your OSPF topology using SNMP as OSPF has an extensive set of MIBs that can be monitored, and there are specific RFCs that describe these MIBs, the most recent of which is RFC 4750 for OSFPv2.
It is indeed a challenge, but with the proper design and the appropriate monitoring tools, it can be achieved.
I hope this has been helpful!
Laz