Hi Mark,
I know it's annoying that I won't mention specifics.Unfortunately, the last time I mentioned $vendor-specific information on NANOG, it was picked up by the press, and turned into a multimillion dollar kerfuffle with me at the center of the cross-hairs:
After that, I've learned it's best to not name specific very-big-name vendors on NANOG posts.
What I *can* say is that this was one of the primary vendors in the Internet backbone space, running mainstream code.The only reason it didn't affect more networks was a function of the particular cluster of signalling communities being applied to all inbound prefixes, and how they interacted with the vendor's hash algorithm.
Corner cases, while valid, do not speak to the majority. If this was a major issue, there would have been more noise about it by now.
I prefer to look at it the other way; the reason you didn't hear more noise about it, is that we stubbed our toes on it early, and had relatively fast, direct access to the development engineers to get it fixed within two days. It's precisely *bcause* people trip over corner cases and get them fixed that they don't end up causing more widespread pain across the rest of the Internet.There has been quite some noise about lengthy AS_PATH updates that bring some routers down, which has usually been fixed with improved BGP code. But even those are not too common, if one considers a 365-day period.
Oh, absolutely. Bugs in implementations that either crash the router or reset the BGP session are much more immediately visible than "that's odd, it's taking my routers longer to converge than it should".
How many networks actually track their convergence time in a time series database, and look at unusual trends, and then diagnose why the convergence time is increasing, versus how many networks just note an increasing number of "hey, your network seems to be slowing down" and throw more hardware at the problem, while grumbling about why their big expensive routers seem to be less powerful than a *nix box running gated?
I suspect there's more of these type of "corner cases" out there than you recognize.It's just that most networks don't dig into routing performance issues unless it actually breaks the router, or kills BGP adjacencies.
If you *are* one of the few networks that tracks your router's convergence time over time, and identifies and resolves unexpected increases in convergence time, then yes, you absolutely have standing to tell me to pipe down and go back into my corner again. ;D