I'm sure I'm not the only one to notice but Facebook dns servers are timing out when requests are sent for its AAAA records. I sent a msg to the Facebook team, hopefully they fix it as this problem adds to page load time, and I shouldn't have to disable ipv6 in my web browser :)
I am not seeing time outs for AAAA recors. Servers seem to respond in less then 350ms.
www.facebook.com. 497 IN NS glb01.sf2p.tfbnw.net.
dig www.facebook.com AAAA @glb01.sf2p.tfbnw.net
;; QUESTION SECTION:
;www.facebook.com. IN AAAA
;; Query time: 252 msec
dig facebook.com NS
;; ANSWER SECTION:
facebook.com. 87070 IN NS dns04.sf2p.tfbnw.net.
facebook.com. 87070 IN NS dns05.sf2p.tfbnw.net.
facebook.com. 87070 IN NS ns1.facebook.com.
facebook.com. 87070 IN NS ns2.facebook.com.
Using "dig facebook.com AAAA @SERVER" those four servers all responded in under 10 milliseconds for me.
dig www.facebook.com NS
;; ANSWER SECTION:
www.facebook.com. 328 IN NS glb01.ams1.tfbnw.net.
www.facebook.com. 328 IN NS glb01.sf2p.tfbnw.net.
www.facebook.com. 328 IN NS glb01.ash1.tfbnw.net.
Using "dig www.facebook.com AAAA @SERVER" those three servers all responded in under 200 milliseconds.
Yeah, looks like its been fixed as far as lookups no longer timing out. Page loads on FB no longer wait on v6 lookups :)
It was horrible... I sent them a message also but I didn't really expect any improvement. I'm rather surprised.