[c-nsp] Ethernet Freezeup

[Andre Beck]

Re Ed,

On Thu, Apr 10, 2008 at 10:14:24AM -0400, Ed Ravin wrote:
> On Thu, Apr 10, 2008 at 01:36:33PM +0200, Andre Beck wrote:
> 
> > Ok, so what's common in *all* these cases is the NPE225. Exactly what
> > I fear is the culprit.
> 
> I guess I should pull the NPE-225 out of my 1750 that was also experiencing
> the problem?

;-)

I currently file this box under "may have been a bad piece of hardware",
as I understood this box showed the problem from the start and replacing
it with a 1720 cleared the issue.

The point with the 7200 chassis, on the other hand, is that all of these
chassis ran great for months or (in my case) even years before the issue
showed up. In my case, it can be directly linked to the NPE replacement,
there was exactly the same traffic before and after the switch and it
*never* even hickupped with the old NPE200. Routing on a stick as hell,
way more than now - I have plugged a lot of static routes to minimize
one-armed routing as much as possible, it's now reduced to actual inter-
VLAN-traffic.
 
> I thought the common factor was the "router-on-a-stick" configuration,
> where traffic is being routed in and out the same interface.

No doubt, this has to be a factor. I'm just getting the impression that
it is only a part of the equation, with other factors beeing relevant.

> Interestingly
> enough, my 7204 was using dot1Q encapsulation to route between multiple
> subinterfaces (which of course was still going in and out the same
> physical interface) while the 1750 did not have subinterfaces but was
> also routing traffic out the same interface that it came in.

My 7206/7204VXR is doing both, with most traffic now beeing inter-VLAN,
and it does route to other interfaces as well. I think router on a stick
is an essential factor here, but it can't be alone.

Thanks,
Andre.
-- 
   Real men don't make backups of their mail. They just send it out
    on the Internet and let the secret services do the hard work.

-> Andre Beck    +++ ABP-RIPE +++      IBH IT-Service GmbH, Dresden <-