[Pkg-utopia-maintainers] Bug#680392: avahi-daemon: Name resolution not working on dual-stack setup on wheezy

Thu Jul 5 15:27:48 UTC 2012

Package: avahi-daemon
Version: 0.6.31-1
Severity: important

Hi,

I'm using avahi-daemon on different hosts, using the full IPv6 and IPv4
resolver (using mdns_minimal and mdns in /etc/nsswitch.conf instead of
mdns4_minimal and mdns4) and I got a problem on wheezy hosts: name
resolution don't work, in the beginning.

For example, resolving from 192.168.122.238 (IPv6
fd76:875a:7e75:0:5054:ff:fe8c:52ed) the name bcama-latitude.local
(192.168.122.1 or fd76:875a:7e75::1) give the following tcpdump trace:

16:09:16.070382 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
16:09:16.070789 IP 192.168.122.238.1024 > 224.0.0.251.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
16:09:16.071012 IP 192.168.122.1.5353 > 192.168.122.238.1024: 0*- 1/0/0 AAAA fd76:875a:7e75::1 (66)
16:09:16.071269 IP 192.168.122.238 > 192.168.122.1: ICMP 192.168.122.238 udp port 1024 unreachable, length 102
16:09:16.140406 IP6 fd76:875a:7e75::1.5353 > ff02::fb.5353: 0*- [0q] 1/0/0 (Cache flush) AAAA fd76:875a:7e75::1 (60)
16:09:16.241617 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:16.241767 IP 192.168.122.238.1024 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:16.241880 IP 192.168.122.1.5353 > 192.168.122.238.1024: 0*- 1/0/0 A 192.168.122.1 (54)
16:09:16.242159 IP 192.168.122.238 > 192.168.122.1: ICMP 192.168.122.238 udp port 1024 unreachable, length 90
16:09:17.242937 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:17.243091 IP 192.168.122.238.1024 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:17.243199 IP 192.168.122.1.5353 > 192.168.122.238.1024: 0*- 1/0/0 A 192.168.122.1 (54)
16:09:17.243424 IP 192.168.122.238 > 192.168.122.1: ICMP 192.168.122.238 udp port 1024 unreachable, length 90
16:09:19.244582 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:19.244783 IP 192.168.122.238.1024 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
16:09:19.244928 IP 192.168.122.1.5353 > 192.168.122.238.1024: 0*- 1/0/0 A 192.168.122.1 (54)
16:09:19.245191 IP 192.168.122.238 > 192.168.122.1: ICMP 192.168.122.238 udp port 1024 unreachable, length 90

>From another host, same debian system (wheezy), but leaving the
mdns4_minimal and mdns4 resolvers (IPv4 only), it works OK:

16:21:09.763775 IP6 fd76:875a:7e75:0:5054:ff:fe50:893a.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
16:21:09.763908 IP 192.168.122.212.5353 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
16:21:09.786172 IP 192.168.122.1.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) A 192.168.122.1 (48)

And from yet another host, with debian squeeze, but the mdns_minimal and
mdns setup (full dual-stack) it works fine too.

16:17:55.882601 IP6 fd76:875a:7e75:0:5054:ff:fe91:7789.5353 > ff02::fb.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
16:17:55.882791 IP 192.168.122.237.5353 > 224.0.0.251.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
16:17:55.882970 IP 192.168.122.1.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) AAAA fd76:875a:7e75::1 (60)
16:17:55.965862 IP6 fd76:875a:7e75::1.5353 > ff02::fb.5353: 0*- [0q] 1/0/0 (Cache flush) AAAA fd76:875a:7e75::1 (60)
16:17:55.984716 IP6 fd76:875a:7e75:0:5054:ff:fe91:7789.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
16:17:55.984843 IP 192.168.122.237.5353 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
16:17:55.984968 IP 192.168.122.1.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) A 192.168.122.1 (48)

The main difference I see is that when using mdns_minimal/mdns and not
the IPv4 one on wheezy, the IPv4 daemon binds itself to port 1024 while
in every other config it binds to 5353. This may be the bug.

If I'm saying “in the beginning”, it's that after some time, it seems to
eventually bind to the correct port:

17:23:41.140960 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
17:23:41.141048 IP 192.168.122.238.5353 > 224.0.0.251.5353: 0 AAAA (QM)? bcama-latitude.local. (38)
17:23:41.141235 IP6 fd76:875a:7e75::1.5353 > ff02::fb.5353: 0*- [0q] 1/0/0 (Cache flush) AAAA fd76:875a:7e75::1 (60)
17:23:41.141408 IP 192.168.122.1.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) AAAA fd76:875a:7e75::1 (60)
17:23:41.242313 IP6 fd76:875a:7e75:0:5054:ff:fe8c:52ed.5353 > ff02::fb.5353: 0 A (QM)? bcama-latitude.local. (38)
17:23:41.242373 IP 192.168.122.238.5353 > 224.0.0.251.5353: 0 A (QM)? bcama-latitude.local. (38)
17:23:41.242537 IP 192.168.122.1.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) A 192.168.122.1 (48)

I don't know why. If I reboot the machine, I get the bug back again.

-- System Information:
Debian Release: wheezy/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-2-amd64 (SMP w/1 CPU core)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages avahi-daemon depends on:
ii  adduser            3.113+nmu3
ii  bind9-host [host]  1:9.8.1.dfsg.P1-4.1
ii  dbus               1.6.0-1
ii  host               1:9.8.1.dfsg.P1-4.1
ii  libavahi-common3   0.6.31-1
ii  libavahi-core7     0.6.31-1
ii  libc6              2.13-33
ii  libcap2            1:2.22-1
ii  libdaemon0         0.14-2
ii  libdbus-1-3        1.6.0-1
ii  libexpat1          2.1.0-1
ii  lsb-base           4.1+Debian7

Versions of packages avahi-daemon recommends:
ii  libnss-mdns  0.10-3.2

Versions of packages avahi-daemon suggests:
pn  avahi-autoipd  <none>

-- no debconf information

-- 
Benjamin Cama <benjamin.cama at telecom-bretagne.eu>