Router / Protocol Problem

Justin M. Streiner streiner at
Wed Sep 6 13:41:47 UTC 2006

On Wed, 6 Sep 2006, Mike Walter wrote:

> I normally would not post to the group, but I am 100% stumped and have
> talked with peers with no luck.
> I have (2) Cisco 7204 Routers running BGP with 3 peers and HSRP.  I am
> not doing anything special with BGP, pretty much a default config that
> has not changed in years.

Please provide details on both your default config and the hardware you're 
using.  You say you have two Cisco 7204s - are these straight '04s, or 
7204VXRs?  What NPE(s) are you using, and how much memory is on them?
The BGP you're getting from your peers - are you getting full routes from 
any of them?  Do you have CEF enabled on these routers?  What IOS 
version(s) are running on these routers?  What else are they doing besides 
slinging BGP routes?  Does the problem go away for a while if you reboot 
one router or the other?

Without knowing any of this, it sounds like you might have NPE-225, -300, 
or -400 with 256 MB of RAM and you are running into memory exhaustion 
issues from carrying full routes.  That's been a pretty popular topic on 
this list and others like cisco-nsp in the last 12 months :)

At a minimum, what do the output of "show mem summary" and "show ip bgp 
sum" from each router show you?

Have you seen other performance problems lately, such as things getting 
mysteriously slower, beyond the rachability issues you mentioned above?
If so, check if CEF is still running (if it was configured in the first 
place).  When a 7200 gets dangerously low on free memory and CEF is 
running, it may cannibalize the IP CEF process to try to conserve memory.
Earlier 12.0 releases did this - I don't know if newer ones still do it.


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