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Linux 小知识 丨用户相关命令

大约 200+ 命令

账号管理

su root

创建用户

useradd [选项] 用户名
# 验证
su 用户名

用户口令(密码)

passwd [选项] 用户名
# 密码不能是一个回文(正读反读都一样的)
# 长度大于8位, 字母数字结合

修改用户

usermod [选项] 用户名
usermod #查看所有选项
Options:
  -c, --comment COMMENT         new value of the GECOS field
  -d, --home HOME_DIR           new home directory for the user account
  -e, --expiredate EXPIRE_DATE  set account expiration date to EXPIRE_DATE
  -f, --inactive INACTIVE       set password inactive after expiration
                                to INACTIVE
  -g, --gid GROUP               force use GROUP as new primary group
  -G, --groups GROUPS           new list of supplementary GROUPS
  -a, --append                  append the user to the supplemental GROUPS
                                mentioned by the -G option without removing
                                the user from other groups
  -h, --help                    display this help message and exit
  -l, --login NEW_LOGIN         new value of the login name
  -L, --lock                    lock the user account
  -m, --move-home               move contents of the home directory to the
                                new location (use only with -d)
  -o, --non-unique              allow using duplicate (non-unique) UID
  -p, --password PASSWORD       use encrypted password for the new password
  -R, --root CHROOT_DIR         directory to chroot into
  -P, --prefix PREFIX_DIR       prefix directory where are located the /etc/* files
  -s, --shell SHELL             new login shell for the user account
  -u, --uid UID                 new UID for the user account
  -U, --unlock                  unlock the user account
  -v, --add-subuids FIRST-LAST  add range of subordinate uids
  -V, --del-subuids FIRST-LAST  remove range of subordinate uids
  -w, --add-subgids FIRST-LAST  add range of subordinate gids
  -W, --del-subgids FIRST-LAST  remove range of subordinate gids
  -Z, --selinux-user SEUSER     new SELinux user mapping for the user account
  
  # 修改用户名 
  usermod -l newUsername oldUsername
  Ctrl + D # 退出用户
  exit # 退出

删除用户

userdel [选项] 用户名
userdel -r -f username

Options:
  -f, --force                   force some actions that would fail otherwise
                                e.g. removal of user still logged in 
                                or files, even if not owned by the user # 强制删除
  -h, --help                    display this help message and exit
  -r, --remove                  remove home directory and mail spool # 删除主目录和邮件池
  -R, --root CHROOT_DIR         directory to chroot into
  -P, --prefix PREFIX_DIR       prefix directory where are located the /etc/* files
  -Z, --selinux-user            remove any SELinux user mapping for the user

用户组

管理员权限

创建用户组

groupadd (选项) 用户组名

修改用户组

groupmod (选项) 用户组名

Usage: groupmod [options] GROUP

Options:
  -g, --gid GID                 change the group ID to GID
  -h, --help                    display this help message and exit
  -n, --new-name NEW_GROUP      change the name to NEW_GROUP # 重命名
  -o, --non-unique              allow to use a duplicate (non-unique) GID
  -p, --password PASSWORD       change the password to this (encrypted)
                                PASSWORD
  -R, --root CHROOT_DIR         directory to chroot into
  -P, --prefix PREFIX_DIR       prefix directory where are located the /etc/* files

查询用户所属组

groups 用户名

[root@VM-8-10-centos ~]# groups root
root : root

删除用户组

groupdel 用户组名

管理用户组内成员 gpasswd

语法

gpasswd (可选项) 组名

gpasswd 是 Linux 下的管理工具, 用于将一个用户添加到组或者从组中删除。

[root@VM-8-10-centos ~]# gpasswd
Usage: gpasswd [option] GROUP

Options:
  -a, --add USER                add USER to GROUP # 添加用户到组
  -d, --delete USER             remove USER from GROUP # 从组删除用户
  -h, --help                    display this help message and exit 
  -Q, --root CHROOT_DIR         directory to chroot into
  -r, --delete-password         remove the GROUP's password # 删除密码
  -R, --restrict                restrict access to GROUP to its members # 限制用户登入组,只有组中成员才可以用newgrp加入该组
  -M, --members USER,...        set the list of members of GROUP # 指定组成员和-A用途相似
  -A, --administrators ADMIN,...
                                set the list of administrators for GROUP # 指定管理员
Except for the -A and -M options, the options cannot be combined.
# 创建用户
[root@VM-8-10-centos ~]# useradd user1
[root@VM-8-10-centos ~]# useradd user2
[root@VM-8-10-centos ~]# useradd user3
# 添加用户到用户组 devgroup
[root@VM-8-10-centos ~]# gpasswd -a user1 devgroup
Adding user user1 to group devgroup
[root@VM-8-10-centos ~]# gpasswd -a user2 devgroup
Adding user user2 to group devgroup
[root@VM-8-10-centos ~]# gpasswd -a user3 devgroup
Adding user user3 to group devgroup
# 验证: grep [组名] /etc/group
[root@VM-8-10-centos ~]# grep 'devgroup' /etc/group
devgroup:x:1004:user1,user2,user3 # 验证成功