Analysis of failing Nagios ping check in Wheezy

[Petter Reinholdtsen <pere@hungry.com>]

Hi.  Just a small update to make sure no-one else waste time
investigating the Nagios failure in the Debian Edu Wheezy build.  I
reported the problem in <URL: http://bugs.debian.org/705900 >, and the
cause is identified.

The problem is that Nagios report that it is unable to ping
tjener.intern using ping6.  The cause is that libnss-myhostname, which
we install everywhere even if it is only useful on laptops, do not
handle IPv6 addresses very well and return a non-working (as in
incomplete) IPv6 address when check_ping and ping6 look up the address
of tjener.intern (on tjener.intern).  This causes ping6 to fail and
Nagios to report an error.

Possible fixes is to change libnss-myhostname to not return incomplete
IPv6 addresses when looking up the current host name.  Another is to
only install the package on Roaming Workstation profiles.  A third is
to disable IPv6 (blacklist the ipv6 kernel module, I guess).

I've asked the maintainer for a change in libnss-myhostname.  If that
do not work out, I suggest we change the package tasks to only install
libnss-myhostname on Roaming workstations.

-- 
Happy hacking
Petter Reinholdtsen