How many routers in an ospf area

[Kashish_Patel]

I am new to OSPF and trying to find a command which can tell "how many routers belong to an area". Is there such a command available?

[Peter Paluch · Accepted solution]

Hello,

I do not think such command is readily available; however, what you can do is to enter the show ip ospf database command and count the entries in the section labeled "Router Link States". Each entry in this section corresponds to one particular router in the corresponding area. Therefore, the number of these router link states (also called Link State Advertisements Type 1, or LSA-1) immediately tells you how many routers are there in the particular area.

Best regards,

Peter

[Kashish_Patel]

Thanks for the reply, Peter. That is certainly what I am looking for! Thanks so much.

[Joseph W. Doherty]

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Posting

The command Peter referenced might have additional options that may limit the output so there's less to look at; i.e. you really don't want to see all the ospf database, just the section of information Peter described.  If not, I recall (?) that's listed first.  (Sorry, at the moment don't have access to any Cisco router to check.)

[Kashish_Patel]

Yes that is listed first in the output.

Thanks.

[Peter Paluch]

Hello Kashish and Joseph,

I was actually looking for a command that displays the count of LSA-1 in the link-state database. That would be completely enough to tell how many routers are there in an area. Sadly, I wasn't able to find it in Cisco IOS CLI (anyone knowing better please share your knowledge!). Also, there is the show ip ospf database router command but that one is going to display the contents of LSA-1 which makes the output even more lengthy. I did not find any other ways of simply and effectively limiting the output so I eventually just stayed with the basic show ip ospf database command.

Best regards,

Peter

[Karsten Iwen · Accepted solution]

What about "sh ip ospf database database-summary"?

Or with more information and counting: "sh ip ospf database router | i Advertising"

[Peter Paluch]

Karsten,

LOL, I must have been blind or something That's it - the show ip ospf database database-summary Thank you so much! Rated as deserved.

Best regards,

Peter