hi readers i am back with informative Linux article. This article is dedicated to those readers who are new to linux and are beginner in this field. Today i am going to share a basic article on how to manage users and groups in Linux.
If you are absolute beginner and do not have much knowledge about user and group management in Linux then after reading this tutorial you got enough knowledge to manage groups and users in a Linux machine.
Note:-> All commands used in this tutorial are valid for Rhel4/5/6/7 ,centOs4/5/6/7 and Fedora.
User management in Linux
Under user management we will learn ==>
How to create a user in Linux?
how to delete a user in Linux?
how to disable a user in Linux?
how to enable a user in Linux?
how to delete password of the user?
how to lock a user in Linux?
how to unlock a user in Linux?
How to add a user in Linux?
Adding a user in linux is very simple. follow simple steps to add a user in linux
Step 1> keep in mind that you are logged in on your linux machine as a root user because only root can add or remove users.
Step 2> now use below command to add a user ==>
Step 3> now its time to give password to the user ==>
How to check details of added user ==>
The output of above command is shown below
Now i will explain every field of above line==>
xyz–> Name of the user
x–> password of user(encrypted)
1004–> User id (UID)-user identification number
1004–> Group id(GID)-is the primary group id.found in the /etc/group file
::–> Comment or description
/home/xyz–> Home directory of the user
/bin/bash–> shell where the program is written.
How to view password related information of users ==>
here password in shown in encrypted form.
How to change password of user ==>
To change the password of a user xyz just use below command ==>
How to delete password of user==>
If you forgot the user password then a root user had a option to remove the password of exiting user==>
#password -d xyz
How to delete a user in Linux
To delete a user in linux you have to use userdel command as shown below==>
Till now we have learned how to add and delete a user, now its time to disable and enable a user.
How to disable a user ==>
If you want to disable a user then use below command
#usermod -s /sbin/nologin <user name>
for e.g. ==> #usermod -s /sbin/nologin xyz
here sbin => a directory which contains system binary files
nologin => this file is responsible to disable a user
How to enable a user ==>
If you want to enable a user then use below command==>
#usermod -s /bin/bash <user name>
#usermod -s /bin/ksh <user name>
#usermod -s /bin/bash xyz
User locking and unlocking in Linux
To lock the user ==>
A locked user can’t login in a Linux system till the root of that Linux system unlock it.
#passwd -l xyz
To unlock the user ==>
#passwd -u xyz
To lock the user==>
#usermod -p “*” <user name>
for e.g. #usermod -p “*” xyz
To unlock the user ==>
Read also ==>
Group management in Linux
Under group management we will learn how to create, delete,and how to add users in a group. ==>
Group creation and deletion in Linux.
Command to add a new group in linux ==>
#groupadd <group name>
for e.g. #groupadd school
how to view status of groups in Linux ==>
To see how many groups are there on your Linux machine use below command ==>
Now let me explain the output of above command ==>
school–> group name
1005–> group id
xyz–> group members or users that are added in the group
How To delete or remove the existing group–>
#groupdel <group name>
How To Add a user in a Group–>
Suppose you have created a user with name xyz and now you have to move this user to the group SCHOOL, then you have to use below command ==>
#usermod -G <group name> <user name>
#usermod -G school xyz
here G= group
In the 2nd part of this tutorial we will learn some advance stuff related to user and group management in Linux. Stay updated and give your feedback if you like his article.