Configuration files, server settings and other files in /etc/ usually owned by root user and require editing for configuration purpose on a Linux or Unix-like systems. You can raise privileges using any one of the following mechanism:
- sudo command : Execute a command as another user using command line method.
- gksudo or gksu command : Execute a command as another user using graphical tool.
Requirements
The normal user needs to be a member of the admin group to raise privileges either via the sudo or gksudo/gksu command. By default, the first user account on a Ubuntu Linux is a member of the admin group. You can verify this by typing the following commands:
## find out your user name ## who am i ## verify that you are part of either sudo or admin group ## id ## Or use /etc/group file to verify that you are part of either sudo or admin group ## egrep -i 'sudo|admin' /etc/group |
Sample outputs:
From the above outputs it is clear that the user named ‘nixcraft’ is part of sudo group on a Ubuntu Linux.
Examples
The nixcraft user is part of the admin or sudo group. All members of the admin group may gain root privileges or allow members of group sudo to execute any command using either CLI or graphical method.
Command line method
The syntax is:
sudo command sudo command arg1 arg2 |
Open the Terminal app and edit file called /etc/resolv.conf either using with nano or vi text editor:
sudo nano /etc/resolv.conf
OR
sudo vi /etc/resolv.conf
You need to provide normal user’s password when prompted:
You can now edit the file and save it as root user. Please note that by default the sudoers policy caches credentials for five minutes i.e. after running sudo the user has five minutes whereby any subsequent sudo invocations do not require the entering of a password. This can be cleared using the following command:
sudo -K |
Graphical method
The syntax is as follows to edit the file /etc/resolv.conf using the gksudo command. First, press ALT-F2 and type the following command in the box (open the terminal app and type the following command):
gksudo gedit /etc/resolv.conf |
Sample outputs:
You need to provide normal user’s password when prompted:
Finally, gedit will open as follows:
See also
- Linux Run Command As Another User – explains use of su and runuser commands on a Linux bases systems.
- Man pages – sudo(8),gksudo(1),gksu(1)
1 comment
You can check in which groups you are by running “groups”, too.