Linux 命令整理 —— 用户管理

浏览数：15 / 时间：2015年06月20日

Linux用户管理以读、写、执行动作为权限，以用户组为单位，限制用户行为。对于文件的的操作，可以限制读、写、执行中的哪一种，也可以限制文件所有者、组用户、组外用户相应的权限。

所以，要建立用户，最好先确定其所在的组。
一、用户组操作
1. 创建用户组——groupadd

```
#新增deploy组  
groupadd deploy  
```

2. 修改用户组——groupmod

#将用户组deploy更名为deploy1  
groupmod -n deploy1 deploy

注意是将已存在的deploy组更名为deploy1

3. 删除用户组——groupdel

#删除用户组deploy1  
groupdel deploy1

4. 查看用户组——groups /etc/group
groups只能查看当前用户所在的组，以下是root用户所在的组。

引用

# groups 
root bin daemon sys adm disk wheel

要看所有用户组信息，直接查看/etc/group：

引用

# cat /etc/group 
root:x:0:root 
bin:x:1:root,bin,daemon 
daemon:x:2:root,bin,daemon 
sys:x:3:root,bin,adm

二、用户操作
1. 创建用户——useradd

引用

# useradd 
Usage: useradd [options] LOGIN 

Options: 
  -b, --base-dir BASE_DIR       base directory for the new user account 
                                home directory 
  -c, --comment COMMENT         set the GECOS field for the new user account 
  -d, --home-dir HOME_DIR       home directory for the new user account 
  -D, --defaults                print or save modified default useradd 
                                configuration 
  -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 for the new user account 
  -G, --groups GROUPS           list of supplementary groups for the new 
                                user account 
  -h, --help                    display this help message and exit 
  -k, --skel SKEL_DIR           specify an alternative skel directory 
  -K, --key KEY=VALUE           overrides /etc/login.defs defaults 
  -m, --create-home             create home directory for the new user 
                                account 
  -l,                       do not add user to lastlog database file 
  -M,                       do not create user‘s home directory(overrides /etc/login.defs) 
  -r,                       create system account 
  -o, --non-unique              allow create user with duplicate 
                                (non-unique) UID 
  -p, --password PASSWORD       use encrypted password for the new user 
                                account 
  -s, --shell SHELL             the login shell for the new user account 
  -u, --uid UID                 force use the UID for the new user account 
  -Z, --selinux-user SEUSER     use a specific SEUSER for the SELinux user mapping

新建用户deploy，位于deploy组，用于部署工作：

#-g 组 用户  
useradd -g deploy deploy

新建用户nginx，位于www组，且不可登录，用于启动nginx：

```
useradd -s /sbin/nologin -g www nginx  
```

为用户deploy设置密码：

引用

# passwd deploy 
Changing password for user deploy. 
New UNIX password: 
Retype new UNIX password: 
passwd: all authentication tokens updated successfully.

新建用户test，位于www组，并为其设置密码为1234567890：

```
useradd -g www -p 1234567890 test  
```

2. 修改用户——usermod gpasswd

引用

# usermod 
Usage: usermod [options] LOGIN 

Options: 
  -a, --append                  append the user to the supplemental GROUPS 
                                (use only with -G) 
  -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 
  -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 
  -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 
  -Z, --selinux-user    new selinux user mapping for the user account