Unable to delete a user from a Linux CentOS 6.3 machine, what can be done?

Question

When I try deleting my user (from a root shell) it says userdel: cannot remove entry 'itaig' from /etc/passwd The user isn't even displayed on /etc/passwd.

[root@ab2c1 ~]# su - itaig
su: warning: cannot change directory to /home/itaig: No such file or directory
-bash-4.1$ exit
logout
[root@ab2c1 ~]# mkdir /home/itaig
[root@ab2c1 ~]# chown itaig.itaig /home/itaig/
[root@ab2c1 ~]# grep itaig /etc/passwd
[root@ab2c1 ~]# grep itaig /etc/shadow
[root@ab2c1 ~]# userdel -rf itaig
userdel: cannot remove entry 'itaig' from /etc/passwd
[root@ab2c1 ~]#

I have the exact same problem in other servers as well but i can't find a common ground between them:

[root@amad ~]# userdel itaig
userdel: cannot remove entry 'itaig' from /etc/passwd
[root@amad ~]# useradd itaig
useradd: user 'itaig' already exists
[root@amad ~]#

How come my user is not displayed in /etc/passwd but still exists on the system? I've checked /etc/nsswitch.conf and found no problem there... What can be done in order to fix this issue?

Edit: The output of strace userdel itaig can be found here: http://pastebin.com/FFkcQ3fj

And the output of strace useradd itaig: http://pastebin.com/twRQ7ps0

Second Edit: It seems that if I manually add my user to /etc/shadow and /etc/group I am then able to delete the user using the command userdel itaig , but even then I'm unable to re-create the user as I get an error that the user already exists. Any help would be appreciated!

[root@ab2c1 ~]# userdel itaig
[root@ab2c1 ~]# useradd itaig
useradd: user 'itaig' already exists
[root@ab2c1 ~]# userdel itaig
userdel: cannot remove entry 'itaig' from /etc/passwd
[root@ab2c1 ~]# grep itaig /etc/passwd
[root@ab2c1 ~]# grep itaig /etc/group
[root@ab2c1 ~]# grep itaig /etc/shadow
[root@ab2c1 ~]# id itaig
uid=509(itaig) gid=510(itaig) groups=510(itaig)
[root@ab2c1 ~]#

Contents of /etc/nsswitch.conf:

passwd:     files   nis
shadow:     files   nis
group:      files   nis
#hosts:     db files nisplus nis dns
hosts:      files nis dns
bootparams: nisplus [NOTFOUND=return] files
ethers:     files
netmasks:   files
networks:   files
protocols:  files
rpc:        files
services:   files
netgroup:   nisplus
publickey:  nisplus
automount:  files nisplus
aliases:    files nisplus

I wonder where the information of the id command comes from:

[root@ab2c1 ~]# grep itaig /etc/passwd
[root@ab2c1 ~]# grep itaig /etc/shadow
[root@ab2c1 ~]# grep itaig /etc/group
[root@ab2c1 ~]# id itaig
uid=509(itaig) gid=510(itaig) groups=510(itaig)
[root@ab2c1 ~]#

What do `getent passwd itaig` and `getent shadow itaig` say? — Etan Reisner, Jul 16 '13 at 13:33
Do you have LDAP authentication configured on this machine? Or some other form of remote directory authentication? — John, Jul 16 '13 at 13:40
Etan: the getent password shows me a line like the ones in /etc/passwd and the getent shadow give me a fresh prompt line without and output — Itai Ganot, Jul 16 '13 at 14:28
Or more likely, `strace useradd itaig`. That should help indicate where/how useradd thinks the user exists. — Christopher Karel, Jul 16 '13 at 15:18
You say you did this from a root shell. Did you originally login as root, or did you log in as itaig and then use sudo to open a root shell? — Jenny D, Jul 18 '13 at 08:38
I logged on initially with root but just to be on the safe side I ran `# pkill -KILL -u itaig` but to no avail. — Itai Ganot, Jul 18 '13 at 08:51
What about name service caching daemons such as nscd or sssd? Try temporarily stopping, or at least restarting, these services after you have removed the user. — Friedrich 'Fred' Clausen, Jul 22 '13 at 08:57

score -1 · Accepted Answer · answered Jul 23 '13 at 03:55

-1

Read up on and try the pwconv, pwunconv and pwck commands to get your passwd and shadow files in sync again. Then try to use your userdel.

Also, is there a reason that you are leaving nis and nisplus defined in your /etc/nsswitch.conf file? I have seen unnecessary naming services cause lag in various functionality due to the fact that they are performing lookups to services that aren't implemented in your environment. I would also clear all of those out to see if you see any improvement in your userdel issue.

answered Jul 23 '13 at 03:55

Tony Cesaro

182
4

4

It seems like I wasn't able to delete the user because it was added on the NIS server... Thanks. – Itai Ganot Aug 01 '13 at 18:48
1

I had a similar issue where the user existed on a SSS server which appears to relate to LDAP. Temporarily removing sss from `/etc/nsswitch.conf` was the solution for me. – bbodenmiller Nov 17 '14 at 01:21
7

'Read up on' isn't an answer. – Stephan Jan 08 '16 at 00:14
1

Just teaching a person to fish. – Tony Cesaro Mar 24 '16 at 20:27
The purpose of stackoverflow/serverfault isn't to teach people how to fish, it's to provide useful answers to questions. – Highway of Life Aug 03 '21 at 04:58

Unable to delete a user from a Linux CentOS 6.3 machine, what can be done?

1 Answers1