Alexei Roudnev wrote:
Purchase SuperMicro U1 server, with 2 9 Gb SCSI
disks (hot swappable).
Suddenly that cheap router ain't cheap anymore.
Now, say, announce A crash Cisco IOS. 99.9% Internet backbones
are Ciscos, so this announce breaks few Ciscos around and die
- so you never know about it (and will not have a chance to be
happy that _this announce crash Ciscos but do not crash ZEBRA).
Not bad, of course - you are alive, all Internet is alive.
Now, say, announce B crash ZEBRA (and do not crash Cisco). It
will spread until it reach first ZEBRA on it;'s road - _your_
ZEBRA. So all Zerbras in Internet crash at once (and you are
Another variant: announcement C crashes vendor "A", but not vendor "B"
and not Zebras either (put whoever you want for "A" and "B" but there's
only two of them on the backbone, mostly). Unfortunately, it takes a few
minutes to crash, so it has enough time to propagate all over the
Internet before the first "A"s begin to crash. As more "A"s crash "B"s
will quickly be overwhelmed and the entire internet soon is down because
no matter who coded it, when half of the backbones takes a hike the
other half follows.
Your Zebra is still up, but it does not do you any good because the
entire Internet is down and you're only a small leaf on its edge, so
nobody knows that you are still up, and they don't care anyway because
no matter what they can't get anywhere.
And yes this happens; not to beat or pick on any of the parties, I
remember the entire AT&T frame relay network being down nationwide for
more than 24 hours (for parts) because (as it is rumored) someone pushed
a bad piece of software on a Stratacom switch.
[me puts the asbestos suit on]
If you have vendor C or vendor J, and all vendor C or J routers crap out
at the same time, you're safe. Yes, you were down but so was half of the
rest of the world, so it's obviously not your fault but vendor C or J's
If you have a zebra one a homebrew PC and all Zebras crap out:
1. You can't blame C or J. Worse, you can't blame anybody else.
2. As a coincidence, a sales droid from C or J will see your boss in the
following days, take him/her to a nice restaurant, and will inevitably
say "this would not have happened if you had a real router instead of
this garage-built crud".
3. The sales droid is full of it, but _you_ are deep into it.
Life is not fair, is it?