USERDEL(8)

名称
userdel - 删除用户账户和相关文件

大纲

userdel [选项] 登录

描述

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

选项

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
    显示帮助信息并退出。

-r, --remove
    用户主目录中的文件将随用户主目录和用户邮箱一起删除。在其它文件系统中的文件必须手动搜索并删除。

    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
    移除用户登录的所有 SELinux 用户映射。

配置文件

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

MAIL_DIR (string)
    邮箱目录。修改或删除用户账户时需要处理邮箱，如果没有指定，将使用编译时指定的默认值。

MAIL_FILE (string)
    定义用户邮箱文件的位置(相对于主目录)。

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

If MAIL_CHECK_ENAB is set to yes, they are also used to define the MAIL environment variable.

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).

    默认值是 0，意味着组中的成员数没有限制。

    此功能(分割组)允许限制组文件中的行长度。这对于确保 NIS 组的行比长于 1024 字符。

    如果要强制这个限制，可以使用 25。

    注意：分割组可能不受所有工具的支持(甚至在 Shadow 工具集中)。您不应该使用这个变量，除非真的需要。

USERDEL_CMD (string)
    如果定义了，这是删除账户时执行的命令。它应该移除所有属于此用户的的 at/cron/print 等作业(作为第一个参数传递)。

    这个脚本的返回值并不被带到账户中去。

    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)
    如果 uid 和 gid 相同，用户名和主用户名也相同，使非 root 组的组掩码位和属主位相同 (如：022 -> 002, 077 -> 007)。

    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.

文件

/etc/group
    组账户信息。

/etc/login.defs
    Shadow 密码套件配置。

/etc/passwd
    用户账户信息。

/etc/shadow
    安全用户账户信息。

/etc/shadow-maint/userdel-pre.d/*, /etc/shadow-maint/userdel-post.d/*
    Run-part files to execute during user deletion. The environment variable ACTION will be populated with userdel and SUBJECT with the username. userdel-pre.d will be executed prior to any user deletion. userdel-post.d will execute after user deletion. If a script exits non-zero then execution will terminate.

/etc/subgid
    Per user subordinate group IDs.

/etc/subuid
    Per user subordinate user IDs.

退出值

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.

您应该手动检查所以文件系统，以确保没有遗留此用户的文件。

您不能在 NIS 客户端上移除任何 NIS 属性。这必须在 NIS 服务器上执行。

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.

参见

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).