UNIX for Dummies Questions & Answers

Now I think you can't edit the file.You need to boot the system from CD in single user mode and then edit both files...

thank you very much "reboot", your responses are absolutely right !

There are two entries for root in /etc/passwd and /etc/group.
This is not correct.

The home directory for root in the first entry in /etc/passwd is wrong (should be /root not root). Hence the "cd" error on "su - root".
The UID for root is wrong (should be zero).
The GUI (in /etc/group) for group root is wrong (should be zero).
This is why "ls -la /root" shows no name for the owner and group.

/etc/passwd
root:x:503:0:root:root:/bin/bash
root:x:503:0:admin:/home/admin:/bin/bash

/etc/group
root:x:503:root,linuxata
root:x:503:root

As there is no user with UID:GROUP values 0:0 you cannot edit /etc/passwd with the system as it stands. As suggested earlier you will need to boot from CD to get a root access so you can correct /etc/passwd.
Then run the checking programs "pwck" and "grpck" until you get a clean result.

The hard bit must be trying to find out what was intended by whoever made the changes and what other random system commands have been typed.

I'd view anything related to the last three lines in /etc/passwd with caution. I don't like the look of the funny characters in the entry for "linuxdata".
fuat:x:501:502:fuat sungur:/home/fuat:/bin/bash
root:x:503:0:admin:/home/admin:/bin/bash
linuxata:x:504:504:türker ata:/home/linuxata:/bin/bash