This is the second time this happened.. (The first was right after I installed, so I just re-installed the system as a fix.-- I'd prefer not to do that.)

I have Mandrake 10.0, everything was working fine, and now I am unable to login as "su". I can logoff and log back in as ROOT, but I can't do any ROOT functions as myself.

Similar to last time, I just downloaded some "security-updates."

Any suggestions?

Hey Darrell, welcome to LQ.org!

Take a look through your /etc directory to see if there's a file called /etc/suauth. This file will limit who can run su, and specifically which users can su to which uids. You can find more info on it by running 'man suauth'.

Also take a look at /etc/login.defs to see what the value of SU_WHEEL_ONLY is. If it is 'yes', then only users who belong to the 'wheel' group can su to root. Again, you can find more info with 'man login.defs'.

BTW when posting a question, try to give as much info as you can. for example, telling us that, 'I am unable to login as "su" ' isn't as helpful as telling us what happens when you try. Also, the first thing to look at when you have a problem is the man page for the problematic command. Running 'man su' will lead you to both of the suggestions I made above.

Enjoy!
--- Cerbere

I found the problem here. Here's what happened for others that may have the same:

I had recently done a CHOWN of the /bin directory so that I could graphically put files in there that I compiled. (I had put a simple C program that I had written in there to be able to execute).

su doesn't like it's permissions/owner changed. So I had to change it back to 04755 using [ ]$CHMOD 04755 su

this fixed the problem.

Hy all, at least someone who has the decint too write how he solved his problem .
I had the same one. And you solved it. :thumbs up:
But i got away with only execution rights for other.(left out read capability). I think main important on this one is the setguid bit.
I´m writing this for security only. So the last advice, definetly make a /etc/suauth file. The man page will tell you how the file has to look alike.

:edit is your option for chmod right (04755). Too me it seems there´s a zero to much? 4755 should be right?!?
Regards zhjim