forcemerge 516218 519774 thanks On Sun, Mar 15, 2009 at 07:20:42AM +0100, Petr Vandrovec wrote: > Hello, > it seems that DNS resolver is grossly confused, and sends > two DNS requests on same socket back to back (strace below is > from 'lynx http://www.jeep.com'). In first one DNS server > responded only to second packet sent by resolver, and resolve > failed (after that mdns was tried, and eventually lynx reported > error that www.jeep.com does not exist). In second one DNS > server responded only to first packet (in my tests I've never > seen DNS server responding to both requests), and although DNS > resolver still uselessly waited for 5 seconds, slowing web browsing > to being almost unusable, after that 5 seconds DNS resolver > declared success, and moved on. > > My /etc/resolv.conf is: > > gwy:~# cat /etc/resolv.conf > domain hsd1.ca.comcast.net. > search hsd1.ca.comcast.net. > nameserver 68.87.76.178 > nameserver 68.87.78.130 > nameserver 68.87.69.146 > gwy:~# > > It seems to be caused by __libc_res_nquery always sending both > T_A and T_AAAA request when T_UNSPEC query is being sent, and > getting confused when only T_AAAA reply arrives. >
The problem is that the DNS server of your ISP does not conform to the RFC and only answer to the AAAA query with a void answer. It never answer to the A query, so the glibc resolver can only conclude the whole query has no answer. This is a known problem, upstream has said he is working on a workaround, but you should definitely talk to your ISP first, as the -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurel...@aurel32.net http://www.aurel32.net -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org