linux-Fifth Lesson Note-[user and user group actions]

User and Group Management commands

Useradd: Used to create a new user

Format: useradd [options] User name

-D Specify the user's home directory

-D Show default values

-e account expiration date, format: Yyyy-mm-dd.

-G Specify an initial user group (must already exist)

-g specifies one or more extended user groups

-N does not create a user group with the same name as the user

-s Specifies the default shell

-U specify UID for user

Instance:

[Email protected] ~]# useradd-d/home/linuxs-u 8888-s/sbin/nologin Linuxs

To view basic information about a user:

[[email protected] ~]# ID Linuxs

uid=8888 (Linuxs) gid=8888 (LINUXS) group =8888 (LINUXS)

passwd: Used to modify the user's password

Format: passwd [options] User name

-l lock User against login

                   -u               unlock to allow users to log on to

                   --stdin       allows user passwords to be modified from standard input, such as (echo "123.com" | passwd--stdin                                                                                                                        Username)

-D make Account no password

-E force user to change password at next logon

-S Displays the user's password status

Instance:

Userdel: Used to delete all user tables

Format: Userdel [options] User name

-F Force removal of users, home directories and their associated files

-R Delete users, home directories and their associated files at the same time

Instance:

[Email protected] ~]# Userdel-r Linuxs

[[email protected] ~]# ID Linuxs

Id:linuxs: No such user

Usermod: Used to modify a user's properties

Format: usermod [options] User name

-C fill in the Account note information

-d-m-M with-D allows you to reassign the user's home directory and automatically transfer the old data to the new home directory

-e account expiry time, format "YYYY-MM-DD"

-G Change the owning user group

-G Change Extended user group

-L lock users against their login system

-U unlocks the user and allows it to log on to the system

-S Change the default terminal

-U modify UID of user

Instance:

[Email protected] ~]# usermod-m-d/home/linuxx linuxs #指定新家目录

[Email protected] ~]# ls/home/

Linuxx

[Email protected] ~]# usermod-u 6666 Linuxs

[[email protected] ~]# ID Linuxs

uid=6666 (Linuxs) gid=8888 (LINUXS) group =8888 (LINUXS)

Groupadd: for creating groups

Format: groupadd [options] Group name

Instance:

[Email protected] ~]# Groupadd Superbsd

Groupdel: Used to delete a group

Format: Groupdel [options] Group name

Instance:

[Email protected]~] #groupdel Superbsd

linux-Fifth Lesson Note-[user and user group actions]