Basic System Administration For Linux

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Step 1. How to turn on the computer and log in.
Step 2. Connecting to the Internet
Step 3. Creating Users
Step 4. How to check your email.
Step 5. Logging off and shutting down the computer
Appendix: A Map of the KDE Desktop.

1. How to turn on the computer

a) Start the computer
b) Log In

a) Starting the Server.

Switching on the power to your computer is simple. Make sure that the computer is plugged into the electrical wall socket. Then press the power button. On most systems, this is on the computer’s front panel. It sometimes is marked with I/O.

b) Logging In

In order to use the computer, you must identify yourself to the system. This is called logging in. When the server has started, a box called a dialog box will appear. System administrators must log in as the root user, the only user authorized to make changes to the way the computer works and recognizes other users.

In the dialog box, type in root in the first field. In the field beneath it, type in the password. When you first get your computers, the password for the root user is password. SchoolNet recommends that you don’t change this password. Once you’ve identified yourself and supplied a password, the computer begins to load the KDE desktop, the screen most users will see most of the time. It’s a graphical user interface. That means that you can use the mouse to point and click to tell the computer what to do.

2. Connecting to the Internet

a) Check the cables
b) Switch the modem on
c) Open the browser
d) Let the modem dial out.

a) To get on the Internet, first check that the modem is plugged into the electrical wall socket and into the phone jack in the wall. Make sure that the modem is connected to the computer via the serial port (a small rectangular block of pins located at the back). There are often several ports of the same kind. Make sure you plug into the one marked COM 1.
b) Turn the modem on. A green light should indicate if it’s getting power.
c) From the desktop, click the icon labelled Web Browser. Your school’s personal web page should begin to load. Once it’s finished, click on one of the links, e.g. The Namibian.
d) Your modem should begin to place a call to SchoolNet’s Internet servers and establish a connection with them. You will hear a range of different sounds. Three green lights will display once the connection has been made. The site whose link you clicked (e.g. The Namibian) should begin to load. You are now connected to the Internet.

Remember: the modem will hang up after three minutes of inactivity.

---! Checking the modem! ----

To get a report of each step that the computer goes through when it’s dialling out, click on the terminal icon and type the following, followed by the enter key.
tailf /var/log/messages

--! Error Messages! ---

2.1: No Carrier Detected. This means that the computer doesn’t register a dial tone on the phone line. Double-check the phone connections. Is the modem connected to the phone line? Is there a dial tone?
2.2: Modem Not Responding. This means that the computer can’t find the modem. Double-check all the connections. Is the computer connected to the modem at COM 1? Is the modem plugged in and switched on?
2.3: Line Is Busy. This means that someone else is on the phone.

3. Creating User Accounts

In order for others to be able to use the computers, the system administrator must first create an account for them. This is done by giving them a user name and a password. This is called creating a user. Only when you are logged in as root or as admin can you create new users. If you log in as admin, click the desktop icon called create a user. Then follow the steps from line 6 of s. a) below.
If you are logged in as root, there are two ways to create users but the first is much easier.

a) Using Tools to create a User.
From the taskbar, click the tools icon. A small menu will pop up. Click on Yast2 Control Center. A new window will appear. On the left hand side of the window, click the item marked Security & Users. (You may have to scroll down to see it.)

The contents of the right side window will change.
Click the icon marked Create A User. It looks like a blue pawn. Next, a form will load. Fill in all the fields and click ‘Create’. You have to enter the password twice, to make sure you have entered it correctly. The system will then save the information and confirm the creation of the account. To create another user, click ‘next’. Close the window by clicking on the ‘x’ in the upper right hand corner or by depressing Alt and F4.

b) Using YaST to create a user.

From the taskbar, click the terminal icon. Type YAST and press the return key. Use the arrow keys to move down to System Administration. Press Enter. Choose User Administration. Fill in the user name and password. Other fields will be filled in automatically. Press F4 to create a user. Press F10 to save and exit. YAST will close automatically.

!-- Users And Email --!

With Linux, the creation of users automatically creates email accounts with the same user name. For example, if you create a user named Sam, that user will have an email account built according to the formula

Username@schoolname.schoolnet.na.

For instance, if Sam is a student at Shikongo Senior Secondary School and has a user name on Shikongo S.S.S.’s computer network, Sam’s email address would be:
Sam@shikongo.shoolnet.na.

4. Configuring (Setting Up) An Email Account.

Squirrel Mail is a web-based email program. That means you can use a browser to read, write and send mail. Because it’s protected by a password, it’s safe to use even on computers used by many different people.To open Squirrel Mail, look on the desktop (click the show desktop icon on the taskbar if it’s not visible) and click on the icon labelled Check Your Email. A web browser window should open and load a login page with some graphics and two text fields. Enter the user name and password. You can also access Squirrel Mail from any open browser window by entering the

following into the location bar of the browser and pressing enter:
http://192.168.0.254/webmail
This will prompt the Squirrel Mail login page to load. Enter the username and password as described above.

5. Logging out and shutting down.

When you want to stop using the computer, you have to tell the computer you’re ending your session. To do this, click start and scroll up to logout. A dialog box will ask you to confirm that you want to stop using the computer. Click OK. Since SchoolNet recommends that the servers and modems be left running day and night, logging out is all users should ever have to do to end their session.
--! Never simply turn the power switch of a running computer. You can damage it severely.
In special cases, such as when the computers are moved, the computer should be shut down.

This is a special process you can do in two ways:
a) Shutting down from the login screen. On the lower right hand side of the login dialog is a pull down menu. Select Shut Down by clicking. The computer will power off.
b) Opening a terminal window via the terminal window icon. Type in halt and press enter.

The User’s Desktop