Bug#667062: could not start fake mpd: Failed to bind to '[::1]:6600': Address already in use

[Niko Tyni]

Package: libtest-corpus-audio-mpd-perl
Version: 1.113282-1
Severity: grave
Tags: ipv6

This package doesn't work at all for me, and it even fails
its test suite when mpd (a missing build dependency) is installed.

  #   Failed test 'module loads ok'
  #   at t/00-compile.t line 17.
  #          got: 'could not start fake mpd: Failed to bind to '[::1]:6600': Address already in use
  # 
  # Compilation failed in require at (eval 4) line 2.
  # BEGIN failed--compilation aborted at (eval 4) line 2.
  # '
  #     expected: ''
  # Looks like you failed 1 test of 1.
  t/00-compile.t ................ 
  Dubious, test returned 1 (wstat 256, 0x100)
  Failed 1/1 subtests 

This happens because share/mpd.conf.template has two bind_to_address
entries:

  bind_to_address      "localhost"
  bind_to_address      "::1"

I ran into this while looking at #665234, and as I didn't get
nearly as far Lucas did in that test suite, I wonder if
this is something specific to my setup. FWIW, my /etc/hosts has

127.0.0.1   localhost
::1     localhost ip6-localhost ip6-loopback

which seems correct to me and is what /var/lib/dpkg/info/netbase.postinst
apparently does for new systems. (See #427067 and #579752.)

Removing the localhost alias from the ::1 entry "fixes" the problem,
but that doesn't seem to be the right way to go.

The sysctl setting net.ipv6.bindv6only doesn't seem to affect this.

All the two packages in sid that build depend on this
(libpoe-component-client-mpd-perl and libaudio-mpd-perl) don't manage
to use it at all here, but skip their relevant tests with the same error
message as above.

Possible fixes could be be changing the first address from localhost to
127.0.0.1 or removing ::1 altogether (as the first one already seems to
achieve the desired result.)

-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)

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

Versions of packages libtest-corpus-audio-mpd-perl depends on:
ii  libfile-sharedir-perl  1.00-0.1
ii  libpath-class-perl     0.25-1
ii  libreadonly-perl       1.03-3
ii  mpd                    0.16.7-2
ii  perl                   5.14.2-9
ii  procps                 1:3.3.2-3

libtest-corpus-audio-mpd-perl recommends no packages.

libtest-corpus-audio-mpd-perl suggests no packages.

-- no debconf information