> For the complete documentation index, see [llms.txt](https://sugar-at.gitbook.io/blog-article/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sugar-at.gitbook.io/blog-article/linux/user-group.md).

# 5.用户管理

## 分类

* 超级用户:root,拥有最高权限 UID:0
* 普通用户:有一定权限限制,可以登录系统:UID:1000-60000
* 系统用户(伪用户):不会登陆系统一般.用于维持某个服务程序UID(1-999)

## 用户相关配置文件

* 账号:/etc/passwd
* 密码:/etc/shadow

## 添加用户

* 命令:useradd
* -u:指定uid
* -d:指定用户主目录
* -g:指定用户组
* -r:指定用户是系统用户
* -s:用户登录shell的解释器
* -M:不创建主目录

## 设置密码

* 命令:passwd username

## 删除用户

* 命令:userdel username

## 添加用户组

* 命令:groupadd

## 删除用户组

* 命令:groupdel


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