It seems that someone upstream of us, but on the same routing hardware at the facility, is suffering a denial of service attack. As a result, you may have been (or may not) experiencing some timeouts or other connectivity issues this afternoon (say, from about 2p ET forward). The good folks at HE and the good Facebook engineers who manage our rack are aware and on the case, and hopefully it will be resolved (by the attack ending or a routing workaround) shortly. In the meantime you should be able to connect to and use the site as you would normally, you may just periodically have to reload a page that stalls. For what it's worth, I haven't noticed any issues in about 10-15 minutes myself, but wanted to post something here acknowledging the issue just as an FYI. Credit to jwinslow for first notification.
