A user in the system needs to be deleted if it's no longer needed, such as when the associated person resigns from a job. If the person is only changing roles, it's better to change the group for the user instead of deleting and creating a new user.

A local user is deleted by removing appropriate entries in user and group-related files such as /etc/passwd, /etc/group, and /etc/shadow. These entries can either be removed manually or by using specialized tools such as userdel.

Using such a tool is always the better option as it reduces errors. When deleting the user, you can also delete files and folders owned by the user, such as the home directory.

Steps to delete user in Linux:

  1. Launch terminal.
  2. Get the list of users for your system.
    $ getent passwd
    root:x:0:0:root:/root:/bin/bash
    daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
    bin:x:2:2:bin:/bin:/usr/sbin/nologin
    sys:x:3:3:sys:/dev:/usr/sbin/nologin
    sync:x:4:65534:sync:/bin:/bin/sync
    games:x:5:60:games:/usr/games:/usr/sbin/nologin
    man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
    lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
    mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
    news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
    uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
    proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
    www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
    backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
    list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
    irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin
    gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin
    nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
    systemd-timesync:x:100:101:systemd Time Synchronization,,,:/run/systemd:/usr/sbin/nologin
    systemd-network:x:101:103:systemd Network Management,,,:/run/systemd:/usr/sbin/nologin
    systemd-resolve:x:102:104:systemd Resolver,,,:/run/systemd:/usr/sbin/nologin
    messagebus:x:103:106::/nonexistent:/usr/sbin/nologin
    syslog:x:104:110::/home/syslog:/usr/sbin/nologin
    _apt:x:105:65534::/nonexistent:/usr/sbin/nologin
    tss:x:106:111:TPM software stack,,,:/var/lib/tpm:/bin/false
    uuidd:x:107:114::/run/uuidd:/usr/sbin/nologin
    tcpdump:x:108:115::/nonexistent:/usr/sbin/nologin
    avahi-autoipd:x:109:117:Avahi autoip daemon,,,:/var/lib/avahi-autoipd:/usr/sbin/nologin
    usbmux:x:110:46:usbmux daemon,,,:/var/lib/usbmux:/usr/sbin/nologin
    rtkit:x:111:118:RealtimeKit,,,:/proc:/usr/sbin/nologin
    dnsmasq:x:112:65534:dnsmasq,,,:/var/lib/misc:/usr/sbin/nologin
    avahi:x:113:120:Avahi mDNS daemon,,,:/run/avahi-daemon:/usr/sbin/nologin
    cups-pk-helper:x:114:121:user for cups-pk-helper service,,,:/home/cups-pk-helper:/usr/sbin/nologin
    speech-dispatcher:x:115:29:Speech Dispatcher,,,:/run/speech-dispatcher:/bin/false
    kernoops:x:116:65534:Kernel Oops Tracking Daemon,,,:/:/usr/sbin/nologin
    saned:x:117:123::/var/lib/saned:/usr/sbin/nologin
    nm-openvpn:x:118:124:NetworkManager OpenVPN,,,:/var/lib/openvpn/chroot:/usr/sbin/nologin
    whoopsie:x:119:125::/nonexistent:/bin/false
    colord:x:120:126:colord colour management daemon,,,:/var/lib/colord:/usr/sbin/nologin
    sssd:x:121:127:SSSD system user,,,:/var/lib/sss:/usr/sbin/nologin
    geoclue:x:122:128::/var/lib/geoclue:/usr/sbin/nologin
    pulse:x:123:129:PulseAudio daemon,,,:/var/run/pulse:/usr/sbin/nologin
    hplip:x:124:7:HPLIP system user,,,:/run/hplip:/bin/false
    gnome-initial-setup:x:125:65534::/run/gnome-initial-setup/:/bin/false
    gdm:x:126:131:Gnome Display Manager:/var/lib/gdm3:/bin/false
    user:x:1000:1000:user,,,:/home/user:/bin/bash
    systemd-coredump:x:999:999:systemd Core Dumper:/:/usr/sbin/nologin
    shakir:x:1001:1001:shakir,,,:/home/shakir:/bin/bash
  3. Force the user to be logged out from the system.
    $ sudo pkill -u shakir
    [sudo] password for user: 
  4. Make sure the user is no longer logged in to the system.
    $ who
    user     :0           2021-01-23 10:28 (:0)
  5. Backup home folder of user or any other files if required.
    $ sudo cp -a /home/shakir /backup-shakir 
  6. Delete user using userdel command.
    $ sudo deluser shakir
    Removing user `shakir' ...
    Warning: group `shakir' has no more members.
    Done.

    Use --remove-home to also remove home directory.

    $ sudo deluser --remove-home shakir
  7. Check if user information still exist just to confirm.
    $ id shakir
    id: ‘shakir’: no such user
    $ grep shakir /etc/passwd
    $ grep shakir /etc/group
    $ ls -l /home
    total 8
    drwxr-xr-x  5 1001 1001 4096 Jan  23 10:46 shakir
    drwxr-xr-x 15 user user 4096 Okt  25 09:28 user

    Home directory should not exist if you previously used --remove-home option.

Discuss the article:

Comment anonymously. Login not required.