Skip to main content

User accounts in Linux

Super User in Linux

Super User is the user with all rights for accessing all files, Like Windows Administrator. Here the super user is "root".

This user have all rights to access all files including system files. Should be careful if you are root. It can delete any files. So it may crash total system.

The root user can be created at the time of installation.

Adding User in Linux

The root user can add user to Linux box. Following command can be used for adding user in Linux.

[root@LocalHost ~]#useradd kumar

For setup password, Following command can be used,

[root@LocalHost ~]#passwd kumar
Changing password for user kumar.
New UNIX password:
Retype new UNIX password:
passwd: all authentication tokens updated successfully.

You'll get a warning message if you give any dictionary word.
"BAD PASSWORD: it is based on a dictionary word"

You can create user without password, also can disable password for a user. Passwordless account.

[root@LocalHost ~]#passwd -d kumar
Removing password for user kumar.
passwd: Success

For more details use man pages of useradd and passwd.

Every user have home directory as the user name, location is /home/{user name}.

Delete User

Following command is used to delete user,

[root@LocalHost ~]#userdel kumar

It delete user alone, home directory will be avaliable in /home/

For delete home diectory of the user, we use the option -r.
For delete the user forcely , we use the option -f.

User Groups

We can add groups in Linux, Groups are used for permission to accessing files and security. Group have one or more users.

For add group,

[root@LocalHost ~]#groupadd adminnote

When we create a user it automatically create group in the same user name. Every users must be in group, Every user have one primary group and may or may not secondary group. For Example, kumar is the user and he should be in the group kumar, It's primary group of the user kumar. And the user kumar may or may not in the group adminnote.

For checking group of the user, try following command.

[root@LocalHost ~]#groups kumar
kumar : kumar

For more details about this refere some Books of Linux.


Popular posts from this blog

Install and Uninstall VMware .bundle in Redhat - RHEL 6

Here the steps for Install and Uninstall VMware .bundle in Redhat and also Linux. I have checked with RHEL 6.

For install :
Login in as root user, Type following command

~]# sh VMware-***.bundle

Here *** will be your software and it's version.

This command will display normal GUI installation. Choose option as your wish.

For Uninstall :
Login in as root user, Type following command

~]# vmware-installer -l

This will display your product name and product version installed by VMware.

Product Name         Product Version    
========== ==============

Note Name and Version, Use following command to uninstall

~]# vmware-installer -u {product-name} {product-version}

~]# vmware-installer -u vmware-workstation

Now you can uninstall with GUI.

* This is common for all VMware .bundle installation files. Ex: VMware-Workstation, VMware-Player etc.

Play NFS (Need For Speed) or other Games on Full Screen in Laptop with Windows 7

Now a days most of people playing NFS serious (NFS Most Wanted , NFS Carbon etc.) in Laptop.

We are facing the problem that NFS game does not play in full screen mode. It have some black bar at both right and left side.

We can fix it with simple steps, For this your video driver should be installed with it's "Graphics & Media Control Panel" application.

Here i have explained it with screen shot. It'll be mostly same for Intel boards. Settings for other video drivers may differ. You may need to search for it in their graphics control panel.

Step 1 :

Click aero button at right bottom corner for show available notifications and running process. There is Graphics & Media Control Panel Icon.
If it is not avaliable there, you can get it from "Windows Control Panel". It'll open your "Graphics & Media Control Panel".

Step 2 :

Click Graphics & Media Control Panel icon and choose Graphics Properties...

Step 3:

Under Intel Graphics and …