Starters for Linux - Part 3

Hi friends! Welcome to the third and final segment of our journey through Linux CLI. We’ll wrap up this series by looking at a number of commands that deal with Basic System Administration and Networking.

Basic System Administration Commands

printtool

(as root in X-terminal) Configuration tool for your printer(s).

To access the settings directly go to the file /etc/printcap.

setup

(as root) Configure the mouse, soundcard, keyboard, X-windows, system services. Works only on Red Hat Linux based systems. Most distributions however ship with a comparable tool, look up the documentation of your distribution.

xvditune

(in X-terminal). Adjust the settings of the graphical display for all resolutions so as to eliminate black bands, shift the display right/left/up/down, etc. (first use the adjustments on your monitor to fit your text mode correctly on the screen). To make the changes permanent, display the frequencies on the screen and transfer them to the setup file /etc/X11/XF86Config.

adduser user_name

Create a new account (you must be root).

E.g., adduser barbara

Don’t forget to set up the password for the new user in the next step. The user home directory is /home/user_name.

passwd

Change the password on your current account. If you are root, you can change the password for any user using:

passwd user_name

useradd user_name

The same as the command adduser user_name .

userdel user_name

Remove an account (you must be root). The users home directory and the undelivered mail must be dealt with separately.

groupadd group_name

Create a new group on your system. Not essential on a home machine with a small number of users.

chmod perm filename

Change the file access permission for the files you own (unless you are root in which case you can change any file). You can make a file accessible in three modes: read (r), write (w), execute (x) to three classes of users: owner (u), members of the same group as the owner (g), others on the system (o).

Check the current access permissions using:

ls -l filename

If the file is accessible to all users in all modes it will show:

rwxrwxrwx

The first triplet shows the file permission for the owner of the file, the second for his/her group, the third for others. A no permission is shown as’ –‘

E.g., this command will add the permission to read the file junk to all (user+group+others)