September 19, 2014

Simple routing mistake breaks Internet on 18-SEP-2014

Did you know the Internet broke down for a bit on 18-SEP-2014?  It's true...and all it took was a simple mistake with a routing table.  Just ask VolumeDrive.  At around 06:49 UTC on 18-SEP-2014, VolumeDrive started advertising to one of it's upstream ISPs (Atrato) all the routes it knew from another one of it's ISPs (Cogent).

How big was the mistake you ask?  Well normally it advertises 39 networks (a.k.a. prefixes) but this time it advertised 400,000...that's 400K networks!  The entire global routing table for the Internet is 500K networks, or 80% of the entire Internet.

The impact was traffic was rerouted through the ISP Atrato erroneously.  Whoops.  And this stuff can easily be done.  A much more detailed (and quite good one I might add) can be found on Renesys' website.  Go have a read.