userdel(8)
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.
-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.
SEE ALSO
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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