userdel
delete a user account and related files
see also :
chfn - chsh - passwd - gpasswd - groupadd - groupdel - groupmod - useradd - usermod
Synopsis
add an example, a script, a trick and tips
examples
source
userdel ossecr; userdel ossecm;
userdel ossec; rm -rf /var/ossec/
source
userdel mailman
groupdel mailman
source
userdel slim
groupdel slim
source
sudo userdel -r 'mpi-cluster-test'
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.
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.
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.
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
files
/etc/group
Group account information.
/etc/login.defs
Shadow password suite configuration.
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
see also
chfn ,
chsh , passwd , login.defs,
gpasswd , groupadd , groupdel ,
groupmod , useradd ,
usermod .