[OPLINLIST] Facebook access restored

[Karl Jendretzky]

All,

There was an issue accessing Facebook when using the state DNS servers starting around 5pm yesterday. 

***As of roughly 8:50am today it seems to be working again.***

If you don't care why, you can stop reading here. :)

So far I've traced it to access to the ip 31.13.71.1 from inside the state network. When loading the main Facebook page it tries to pull data from a CDN server at star.c10r.facebook.com. CDN server DNS entries respond with different ip addresses depending on the network location of the client making the request. When the state DNS servers request that domain they get 31.13.71.1, but when outside public DNS servers query they get 31.13.74.1 (this is normal). During the outage inside the state network the ip 31.13.74.1 was available but 31.13.71.1 was not. From my home TWC connection 31.13.71.1 was available. 

Analyzing the path to 31.13.71.1 showed us leaving the OPLIN network, traversing OARNET and Internet2 networks, and then stopping a couple hops from Facebook's edge in some Texas based network. Now that access is restored the trace completes successfully.

Considering this was way outside my network I don't expect to get any additional info, but I figured I'd share what I know. 

Karl Jendretzky
Technology Manager
Ohio Public Library Information Network
jendreka at oplin.org
(614) 728-1515