Ubuntu Manpage: userdel - delete a user account and related files

Provided by: passwd_4.8.1-1ubuntu5.20.04.5_amd64

NAME

       userdel - delete a user account and related files

SYNOPSIS

       userdel [options] LOGIN

DESCRIPTION

       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.

OPTIONS

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 manually.

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.

-P, --prefix PREFIX_DIR
Apply changes in the PREFIX_DIR directory and use the configuration files from the
PREFIX_DIR directory. This option does not chroot and is intended for preparing a
cross-compilation target. Some limitations: NIS and LDAP users/groups are not
verified. PAM authentication is using the host files. No SELINUX support.

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

CONFIGURATION

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.

MAX_MEMBERS_PER_GROUP (number)
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
fi

# 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.
AT_SPOOL_DIR=/var/spool/cron/atjobs
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.

FILES

       /etc/group
           Group account information.

       /etc/login.defs
           Shadow password suite configuration.

       /etc/passwd
           User account information.

       /etc/shadow
           Secure user account information.

       /etc/subgid
           Per user subordinate group IDs.

       /etc/subuid
           Per user subordinate user IDs.

EXIT VALUES

       The userdel command exits with the following values:

       0
           success

       1
           can't update password file

       2
           invalid command syntax

       6
           specified user doesn't exist

       8
           user currently logged in

       10
           can't update group file

       12
           can't remove home directory

CAVEATS

       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 account.

       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.