[c-nsp] Cisco 3550-12G VSI stops routing traffic

[randal k]

I thought so too, except that we have < 3% CPU usage; we have other 3550s
with 30+ VSI interfaces moving considerably more traffic without issue. The
anecdotes I've read say that # of routes is what makes them fall over, and
we're not even close.

1- u mentioned u transferred the affected VLANs to another distribution
> switch , what is the active number of VLANs on this switch ? 2- as i got
> from ur description , the switch always drops the traffic of only 2
> VLANs randomly . get the output of show vlan and show spanning tree during
> the problem time
> 3- u mentioned that the problem solved when u cleared ARP table , can u
> get show arp | in incomplete to see which entries are incomplete before and
> after the clearing and which VLAN it belongs to .
>

1. The alternate switch has the exact same # of VLANs as these particular
two switches see just about everything on our network. The alternate happens
to run c3550-i5q3l2-mz.121-22.EA5 though. Total # of VLANs on both is 86.
2. I immediately checked show vlan & show spanning-tree vlan XYZ to make
sure that we didn't lose the VLANs from the trunks -- they're still there.
The VSI stays up as well, which lets OSPF keep the route in place.
3. I wish I could give you one from when things were broken; as of right now
(with the ?broken? g0/4 unused) I have zero incompletes.

We had a problem that might be similar to this with our 3550 CPEs some time
> ago. All our affected SVIs were configured with VRF Lite.
>
We are not using VRF lite anywhere; only place we use VRF (exactly one
instance) is on our core 6509s.

Are you using route authentication?
>
Nope.

I do appreciate the input, this one me stuck. Hopefully the existing bypass
of g0/4 will let me get some sleep and not make me tear my hair out tomorrow
morning between 9 & 10am :)

Cheers,
Randal