Created attachment 374274 [details] emerge --info Name resolution failed after emerge of glibc to Gentoo 2.19 p1. Name resolution is restored on that version after I remove the following option line from my /etc/resolv.conf: options edns0 rotate ipv6 timeout:10 attempts:3 This options line has worked in previous ~x86 glibc's. Attached is my emerge --info
I could duplicate this on a host running a nameserver. With the options line a "ping" request gives unknown host. However dig seemed to be able to resolve properly even with the options line in resolv.conf.
The bug seems triggered when I have my resolv.conf starting with a nameserver ipv6 address. Putting the nameserver statement that has the ipv6 address second or third down seems to work with the options rotate. Just fyi here is a resolv.conf that triggers the bug: nameserver 2001:470:a00f::1 nameserver 192.58.220.65 nameserver 192.58.220.5 domain wraith.sf.ca.us options edns0 rotate ipv6 timeout:10 attempts:3 Either removing the rotate from options or moving the ipv6 nameserver statement other than first allows dns to resolve again. This hit me after a world emerge that pulled glibc and other stuff. After the glibc update was installed name resolution failed--no more ftp's worked in the emerge, for instance.
I'm also seeing this problem when I have a mixture of IPv4 and IPv6 nameservers in resolv.conf (no 'rotate' options, though) - and the fix does appear to be to put an IPv4 entry first. (I note that the vim syntax-highlighter for resolv.conf highlights IPv6 addresses as if they were errors. This is probably just not updated for IPv6 entries, but I'm wondering whether it knows something I don't...)
Looks like upstream has verified this: Sourceware Bugzilla – Bug 17053 IPv6 name server support is broken
should be fixed w/glibc-2.22 which is in the tree now
