


How to create a user and specify a user group in Linux
May 17, 2023 pm 10:55 PMlinuxCreate a user and specify a user group
1. View all users
cat /etc/passwd
groupadd zhangsangroup #創(chuàng)建用戶組zhangsangroup
useradd -g zhangsan zhangsan 創(chuàng)建用戶zhangsan并加入zhangsangroup組
useradd parameters:
-u UID
: Specify UID, this UID must be greater than or equal to 500, and there is no UID occupied by other users
-g GID
/
GROUPNAME: Specify the default group, which can be GID or GROUPNAME, and must also exist
-G GROUPS
: Specify additional groups
-c COMMENT
: Specify the user’s comment information
-d PATH
: Specify the user’s home directory
useradd user3 #新增用戶 usermod –l u1 user1 #將用戶user1的登錄名改為u1 usermod –d /users/us1 user1 #將用戶 user1家目錄改為/users/us1 usermod –g users user1 #將用戶user1加入到 users組中, userdel user3 #刪除用戶 userdel –r user3 #刪除用戶并刪除家目錄 groupadd users #添加一個用戶組users groupmod –n user users #修改組名user為users groupdel users 刪除組users# The
- ##id
command can view the UID and GID of a user, for example: id user4
- finger
command can view the user’s main Directory, startup shell, user name, address, phone number and other information. Example: finger user4
##groups - command to view the groups to which the user belongs, for example: groups root
2. Use the gpasswd command to add users to the group.
gpasswd –a user1 users #把 user1加入users組 gpasswd –d user1 users #把 user1退出users組3. Modify file permissions chmod
chmod -R 777 /var/lib/mysql #表示修改文件為最高權限-R means processing all files in the specified directory and its subdirectories4. Modify the user and group chown of the file (note: the owner is first, the group is last)
chown -R mysql:mysql /var/lib/mysqlFormat: chown [option]...[owner][:[group]] File...-R means to process all files in the specified directory and its subdirectorieslinuxCreate a user and determine the group the user belongs to1. Create the group monster
[root@zhz home]# groupadd monster
2. Create the user tom, and the group tom belongs to is monster[root@zhz home]# useradd -g monster tom
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