A while back I was trying to set up kpropd on a Debian system, and came across a problem whereby one of my hosts was identifying itself as host/localhost.localdomain (this was Not Helpful).

Investigation revealed firstly that hostname returned the correct thing (i.e. servername), and secondly that /etc/hosts looked like this:

x.x.x.x     servername.mydomain.com  servername
127.0.0.1    localhost.localdomain  localhost  servername

There has been discussion on the Debian lists about the order of this last line being incorrect; some applications (including, it seems, at least some aspects of Kerberos admin) can’t cope with 127.0.0.1 returning localhost.localdomain instead of localhost.

Replacing that last line with

127.0.0.1    localhost  localhost.localdomain  servername
solved the problem - i.e. localhost.localdomain wants to be an alias, not the canonical hostname.

(Note: this was using a sarge system (and in fact I was working on this quite some time ago); I don’t know what the current situation is with etch, nor whether it has been fixed in recent sarge bugfixes. Just documenting it in case others encounter the same/similar problem.)