interpreting show ip eigrp traffic output

[tato386]

I am troubleshooting some issues with an EIGRP based network that is experiencing intermittent outages.  The attached file is the "show ip eigrp traffic" output from a few of the routers.   The SIA queries and replies concern me but I am not sure on how to interpret them.  The command references just say the numbers show  amount of  SIA replies and queries sent and received!  That of course is obvious from the output but what does it tell me about the status of my network?  Thanks

[John Blakley]

Queries are the result of a router losing a route and then querying a neighbor for a backup route. If the neighbor that it queried doesn't respond in a timely fashion, the router goes SIA for the route and removes the neighbor that didn't respond to the query. It's hard to tell you from this output why the problem is happening. The first thing you may want to do is look at congestion in your network to see if that could be a factor as to why the queries aren't getting back. The timer is about 3 minutes for a reply to be received.

Here's a document that explains a couple more reasons:

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a008010f016.shtml

HTH,

John

[tato386]

I will definitely check out the link.  It looks very helpful.  But before I venture into why routes go SIA.  I want to understand what the output is telling me.  So for instance if I take R2 as en example it shows:

  SIA-Queries sent/received: 351/0

  SIA-Replies sent/received: 0/314

So this would mean that this router sent out 351 SIA queries but only received 314 replies. So that in 37 instances it did not receive a reply and therefore dropped the nieghbor it queried.

This would also show that this router received 0 queries and therefore never had to send a reply.  Is this correct?  TIA

[John Blakley]

In your posting above:

  SIA-Queries sent/received: 351/0

  SIA-Replies sent/received: 0/314

This indicates that this one router has went active on a route and queried for the route 351 times (not necessarily the same route) and it's received 314 replies from these queries. (Just like you said.) And, yes, from the output it doesn't look like it's ever been queried. A good place to start would be to look at the topology table and see if you have routes on this router that are successors that should be. If you have some routes that you think should be in there, and they're not, then you probably need to look a little deeper into your topology.

HTH,

John

[dslice]

A reply will also stop the query process, so it's possible that some of these SIA Queries were answered with replies rather than Just SIA Replies.

Sent from Cisco Technical Support iPad App

[tato386]

Thanks guys for all the good input.

Rgds,

Diego