userdel - delete a user account and related files


   userdel [options] LOGIN


   userdel is a low level utility for removing users. On Debian,
   administrators should usually use deluser(8) instead.

   The userdel command modifies the system account files, deleting all
   entries that refer to the user name LOGIN. The named user must exist.


   The options which apply to the userdel command are:

   -f, --force
       This option forces the removal of the user account, even if the
       user is still logged in. It also forces userdel to remove the
       user's home directory and mail spool, even if another user uses the
       same home directory or if the mail spool is not owned by the
       specified user. If USERGROUPS_ENAB is defined to yes in
       /etc/login.defs and if a group exists with the same name as the
       deleted user, then this group will be removed, even if it is still
       the primary group of another user.

       Note: This option is dangerous and may leave your system in an
       inconsistent state.

   -h, --help
       Display help message and exit.

   -r, --remove
       Files in the user's home directory will be removed along with the
       home directory itself and the user's mail spool. Files located in
       other file systems will have to be searched for and deleted

       The mail spool is defined by the MAIL_DIR variable in the
       login.defs file.

   -R, --root CHROOT_DIR
       Apply changes in the CHROOT_DIR directory and use the configuration
       files from the CHROOT_DIR directory.

   -Z, --selinux-user
       Remove any SELinux user mapping for the user's login.


   The following configuration variables in /etc/login.defs change the
   behavior of this tool:

   MAIL_DIR (string)
       The mail spool directory. This is needed to manipulate the mailbox
       when its corresponding user account is modified or deleted. If not
       specified, a compile-time default is used.

   MAIL_FILE (string)
       Defines the location of the users mail spool files relatively to
       their home directory.

   The MAIL_DIR and MAIL_FILE variables are used by useradd, usermod, and
   userdel to create, move, or delete the user's mail spool.

       Maximum members per group entry. When the maximum is reached, a new
       group entry (line) is started in /etc/group (with the same name,
       same password, and same GID).

       The default value is 0, meaning that there are no limits in the
       number of members in a group.

       This feature (split group) permits to limit the length of lines in
       the group file. This is useful to make sure that lines for NIS
       groups are not larger than 1024 characters.

       If you need to enforce such limit, you can use 25.

       Note: split groups may not be supported by all tools (even in the
       Shadow toolsuite). You should not use this variable unless you
       really need it.

   USERDEL_CMD (string)
       If defined, this command is run when removing a user. It should
       remove any at/cron/print jobs etc. owned by the user to be removed
       (passed as the first argument).

       The return code of the script is not taken into account.

       Here is an example script, which removes the user's cron, at and
       print jobs:

           #! /bin/sh

           # Check for the required argument.
           if [ $# != 1 ]; then
                echo "Usage: $0 username"
                exit 1

           # Remove cron jobs.
           crontab -r -u $1

           # Remove at jobs.
           # Note that it will remove any jobs owned by the same UID,
           # even if it was shared by a different username.
           find $AT_SPOOL_DIR -name "[^.]*" -type f -user $1 -delete \;

           # Remove print jobs.
           lprm $1

           # All done.
           exit 0

   USERGROUPS_ENAB (boolean)
       If set to yes, userdel will remove the user's group if it contains
       no more members, and useradd will create by default a group with
       the name of the user.


       Group account information.

       Shadow password suite configuration.

       User account information.

       Secure user account information.

       Per user subordinate group IDs.

       Per user subordinate user IDs.


   The userdel command exits with the following values:


       can't update password file

       invalid command syntax

       specified user doesn't exist

       user currently logged in

       can't update group file

       can't remove home directory


   userdel will not allow you to remove an account if there are running
   processes which belong to this account. In that case, you may have to
   kill those processes or lock the user's password or account and remove
   the account later. The -f option can force the deletion of this

   You should manually check all file systems to ensure that no files
   remain owned by this user.

   You may not remove any NIS attributes on a NIS client. This must be
   performed on the NIS server.

   If USERGROUPS_ENAB is defined to yes in /etc/login.defs, userdel will
   delete the group with the same name as the user. To avoid
   inconsistencies in the passwd and group databases, userdel will check
   that this group is not used as a primary group for another user, and
   will just warn without deleting the group otherwise. The -f option can
   force the deletion of this group.


   chfn(1), chsh(1), passwd(1), login.defs(5), gpasswd(8), groupadd(8),
   groupdel(8), groupmod(8), subgid(5), subuid(5), useradd(8), usermod(8).


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