Your message dated Sat, 11 Jan 2025 12:21:30 +0100 with message-id <[email protected]> and subject line Re: Bug#776994: not on jessie has caused the Debian Bug report #776994, regarding Random DNS lookup failure when mixing IPV6 and IPV4 resolver and using rotate option on /etc/resolv.conf to be marked as done.
This means that you claim that the problem has been dealt with. If this is not the case it is now your responsibility to reopen the Bug report if necessary, and/or fix the problem forthwith. (NB: If you are a system administrator and have no idea what this message is talking about, this may indicate a serious mail system misconfiguration somewhere. Please contact [email protected] immediately.) -- 776994: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=776994 Debian Bug Tracking System Contact [email protected] with problems
--- Begin Message ---Package: eglibc Version: 2.13-38+deb7u7 When setting a Postfix server for outgoing mail using a very simple configuration, I had issues resolving MX entries on the postfix logs like : Feb 3 20:11:06 londo postfix/smtp[4288]: 3CB504BE8: to=<[email protected]>, relay=none, delay=0.06, delays=0.04/0.01/0/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for name=bar.com type=MX: Host not found, try again). This resolving issue was random (About one of the two tests) The configuration in /etc/resolv.conf was the following : nameserver <IPV6 resolver> nameserver <IPV4 resolver> nameserver <IPV4 resolver> options timeout:1 attempts:3 rotate The three resolvers are OK : I queried them independently and they answer perfectly so it's not a resolver issue. After lots of investigations, I isolated the following behaviour : There is no resolving issue when removing the rotate option OR when putting the IPV6 resolver after the IPV4 ones. Browsing on the Web, a chat partner (Thanks Stephane) found this bug on Redhat/Fedora distributions : https://bugzilla.redhat.com/show_bug.cgi?id=841787 which seems to be similar to my bug. A patch has been applied to the Fedora / RH distributions. This patch is described here: http://pkgs.fedoraproject.org/cgit/glibc.git/tree/glibc-rh841787.patch?h=f17. I updated the patch for the eglibc since a part of the patch was already into the debian patches series (any/submitted-resolv-init.diff) and recompiled a package. After installation, it seems that the issue was solved : The DNS resolution was 100 % OK. I send the patch as attachement. (I'm not a low level C developper so i hope this patch is not too ugly) Thanks ! Regards, Olivier Bonhommediff -rup a/resolv/res_init.c b/resolv/res_init.c --- a/resolv/res_init.c 2012-07-26 15:10:45.655638776 -0600 +++ b/resolv/res_init.c 2012-07-26 15:11:27.731423002 -0600 @@ -314,9 +314,9 @@ __res_vinit(res_state statp, int preinit cp++; if ((*cp != '\0') && (*cp != '\n') && __inet_aton(cp, &a)) { - statp->nsaddr_list[nservall].sin_addr = a; - statp->nsaddr_list[nservall].sin_family = AF_INET; - statp->nsaddr_list[nservall].sin_port = + statp->nsaddr_list[nserv].sin_addr = a; + statp->nsaddr_list[nserv].sin_family = AF_INET; + statp->nsaddr_list[nserv].sin_port = htons(NAMESERVER_PORT); nserv++; #ifdef _LIBC diff -rup a/resolv/res_send.c b/resolv/res_send.c --- a/resolv/res_send.c 2010-05-04 05:27:23.000000000 -0600 +++ b/resolv/res_send.c 2012-07-26 15:34:58.398261659 -0600 @@ -421,10 +421,10 @@ __libc_res_nsend(res_state statp, const EXT(statp).nsmap[n] = MAXNS; } } - n = statp->nscount; - if (statp->nscount > EXT(statp).nscount) + n = statp->nscount - EXT(statp).nscount6; + if (n > EXT(statp).nscount) for (n = EXT(statp).nscount, ns = 0; - n < statp->nscount; n++) { + n < statp->nscount - EXT(statp).nscount6; n++) { while (ns < MAXNS && EXT(statp).nsmap[ns] != MAXNS) ns++;
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--- Begin Message ---Version: 2.19-2 Hi, On 2015-05-01 17:18, Raphaël Droz wrote: > Just upgraded to Jessie today (libc 2.19-18) and I can't reproduce the bug. > (while Wheezy-only, it's still an important isn't?) Indeed, you are correct, a fix for that went into glibc 2.19-2. Closing the bug accordingly: * debian/patches/any/submitted-resolv-ipv6-nameservers.diff: new patch to fix resolving issues when using IPv6 nameservers in resolv.conf. Closes: #627531, #644406, #709867. Regards Aurelien -- Aurelien Jarno GPG: 4096R/1DDD8C9B [email protected] http://aurel32.net
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