[c-nsp] 2970 turns into a hub for a few moments

[Vincent De Keyzer]

>     http://www.cisco.com/warp/public/473/143.html
> 
> This document describes all of the possibilities mentioned so far;
> "Cause 2" is what I'm guessing your problem is.

Well, since there have been no topology changes, and we have a dual firewall
set-up, I will more likely investigate cause 1 (asymmetrical routing).

Thanks for the hint, I'll post again when I have found the answer...

Vincent