Facebook 503 502 Same html different servers different results

Question

I've got the same html on two separate Mediatemple (DV) servers and one Godaddy server. Godaddy resolves quickly and both Mediatemple server fail with 502 when run though Facebook debugger.

Mediatemple (DV). http://www.site500.com/facebook.html

Godaddy http://www.trainlearncreate.com/facebook.html

Also my server access logs do not register a hit by Facebook when the 502 is returned.

Answer 1

Godaddy http://www.trainlearncreate.com/facebook.html

That page has it's og:url set to http://www.trainlearncreate.com/facebook.html

Mediatemple (DV). http://www.site500.com/facebook.html

That page has it's og:url set to http://site500.com/facebook.html

Currently the second page is working for me in the debug tool as well - but if you maybe had a non-www-to-www-redirect in place, this would lead to a redirect circle, since Facebook tries to retrieve the OG info from the address given as og:url.