Linux系統三類用戶身份---uid

1. 管理員 0，默認用戶名稱root
    
2. 系統用戶 rhel5/6 1-499 rhel7 1-999，特定服務的系統用戶，特點權限比較小
    
3. 普通用戶 rhel5/6 1000-65535 rhel7 1000-+

[root@localhost Desktop]# useradd -u 8888 lence.zhou
[root@localhost Desktop]# id lence.zhou
uid=8888(lence.zhou) gid=8888(lence.zhou) groups=8888(lence.zhou)

 
修改用戶的uid
usermod -u 666666 xiaozhang

[root@localhost Desktop]# id xiaozhang
uid=666666(xiaozhang) gid=1005(xiaozhang) groups=1005(xiaozhang)
[root@localhost Desktop]# usermod -u 666666 xiaozhang
usermod: no changes
[root@localhost Desktop]# id xiaozhang
uid=666666(xiaozhang) gid=1005(xiaozhang) groups=1005(xiaozhang)

 
添加擴展組
usermod -G itgroup xiaozhang

[root@localhost Desktop]# id xiaozhang
uid=666666(xiaozhang) gid=1005(xiaozhang) groups=1005(xiaozhang)
[root@localhost Desktop]# usermod -G itgroup xiaozhang
[root@localhost Desktop]# id xiaozhang
uid=666666(xiaozhang) gid=1005(xiaozhang) groups=1005(xiaozhang),8889(itgroup)

 
修改基本組
usermod -g 基本組 xiaozhang

 
用戶組
創建用戶組 groupadd

 
刪除用戶組裏的用戶，dd命令
vim /etc/group

 
刪除用戶
userdel xiaozhang
cd home目錄，把xiaozhang的目錄刪掉

userdel -r zhangsan，徹底將用戶及其家目錄刪掉

[root@localhost Desktop]# userdel xiaozhang
[root@localhost Desktop]# cd /home/
[root@localhost home]# ls
admins     jack        natasha      sudan.lu      xiaotong
bugle.pan  lence.zhou  ronny        wangwu        xiaozhang
cici.liu   linuxprobe  sampson.qiu  wwwroot       zhangsan
harry      lisi        sarah        xiangxi.kong
[root@localhost home]# userdel -r zhagnsan
userdel: user 'zhagnsan' does not exist
[root@localhost home]# userdel -r zhangsan
[root@localhost home]# ls
admins     harry       linuxprobe  ronny        sudan.lu  xiangxi.kong
bugle.pan  jack        lisi        sampson.qiu  wangwu    xiaotong
cici.liu   lence.zhou  natasha     sarah        wwwroot   xiaozhang