su does not work anymore

[Rainer Dorsch <contact@bokomoko.de>]

Hello,

I had an accidential / in a 

# chown -R install-user /xyz/dfak /

command. Changing the ownership / recursively is certainly not a good idea.

I did revert this by 

#chown -R root /etc /bin /usr ...

(all directories why were owned by install-user).

That was certainly overdone, so I used

find . \! -user root -print

on another system with a similar package list to get a list of files which are 
not owned by root.

What still does not work is "su -".

The log in /var/log/auth.log is given by

May  1 22:07:46 h370 unix_chkpwd[12768]: check pass; user unknown
May  1 22:07:46 h370 unix_chkpwd[12768]: password check failed for user (root)
May  1 22:07:46 h370 su: pam_unix(su-l:auth): authentication failure; 
logname=rd uid=2809 euid=2809 tty=pts/0 ruser=rd rhost=  user=root
May  1 22:07:48 h370 su: FAILED SU (to root) rd on pts/0

root login on a console works.

Any suggestion to find out what goes wrong (and avoid reinstallation) is 
welcome :-)

Thanks
Rainer


-- 
Rainer Dorsch
Beatus-Widmann-Str. 5
72138 Kirchentellinsfurt
07157/734133