Linux User and user group management

The user information created by/ETC/PASSWD will be displayed in this directory

1th paragraph: User name

2nd: Password, later placed in/etc/shadow

3rd paragraph: UID

4th paragraph: GID

5th paragraph: General user is generally empty, can write explain explanation

6th paragraph: Home directory

7th paragraph: Shell

/etc/shadow where the user's password exists

① User Name

② User Encrypted password

③ from January 1, 1970 to the last time the password was modified

④ password How many days to modify

⑤ How long will the password expire

⑥ How many days before the password expires alert

⑦ the number of days after the password expires lock account

⑧ Account life cycle

⑨ Reserved values

User Group Management

#groupadd GRP1 #增加一个grp1的用户组

#groupadd-G 1005 Grp2 #增加一个grp2用户组 and specifies a GID of 1005

#groupdel GRP1 #删除一个grp1用户组

Delete a group be sure that there are no group users in the group

User Management

#useradd User2 #增加一个user2的用户

#useradd-U 1004-g 1005 user3 #增加一个user3用户并指定uid为1004 GID is 1005

#useradd-u 1005-g 1005-d/home/zhdyaa-s/sbin/nologin user5 @ Adds a user5 with a custom UID of 1005 GID of 1005 (multiple users can join the same group), home directory /zhdyaa Parameters ~

#useradd-M User6 #增加一个user6 but do not create home directories

#userdel-R User5 #删除用户的同时, along with home directory also deleted!

This article is from the "Old seven Linux Operations Management" blog, please be sure to keep this source http://asd9577.blog.51cto.com/4291946/1934619

Linux User and user group management