[c-nsp] EIGRP flapping

[aaron]

Hi Guys,

 

This is our setup. We have two 6500 series with Sup2's with 4 1gig bundled
links in an etherchannel trunk configuration. Both have the same VLAN
interfaces with HSRP configured for the various VLAN's. EIGRP is configured
and is establishing neighbours on each VLAN. We are having a weird problem
where the CPU will jump to 100% only briefly and EIGRP will flap every 5
seconds for these connected routes. We suspected that there might be
something flakey about the etherchannel configuration but no errors or
transitions are noticeable with the etherchannel bundle or any of the
physical interfaces.

 

What is confusing is why the EIGRP routes are flapping every 5 seconds..
Isnt the normal hello timer meant to be 5 seconds and shouldn't the switches
wait 3x Hello before declaring the EIGRP neighbours down? Maybe the
multicasts are causing the CPU spikes?? 

 

Anyone experienced similar issues?

 

Cheers,

 

Aaron.