Oh well... today I upgraded a server at my workplace from Sarge to Etch. This went fairly well EXCEPT that the machine was quite slow afterwards and Samba didn't work anymore. No problem, I thought, because during the upgrade the Samba was displaying a note that I'll need to change the passdb line, because it doesn't support chained backend lists anymore.
The problem was, that this didn't help. To make a long story short:
During the upgrade the file /etc/libnss-ldap.conf has been overwritten without any notification. There's even no /etc/libnss-ldap.conf.dpkg-old file.
Apparently the QA of the Etch release failed in this particular case. Am I the only one who's using LDAP?
Meebey hinted me to have a look at the config file. The problem is, that the config file has a Debconf header, which indicates that it is handled by debconf. I'm used to edit those files anyway, because usually debconf (or the package scripts) notices if the file was changed manually and gives a warning about this issue. Well, the libnss-ldap package seems to be rather dumb and doesn't recognize when something has been changed within its configuration file. So, removing the debconf header will prevent this from happening again. Thanks, Meebey!