This article focuses becoming familiar with a standard Linux Installation, and covers tasks such as logging on, exploring the file system, and accessing system resources, such as your CD-ROM drive. It also discusses basic console commands and the use of vi.
Linux requires that every user be identified by a username and password. During most installation programs, you have the option of creating user accounts, which can be used to log onto the system. You can also log on as root, using the password you specified during setup. If you log on as root, be very careful as root has unlimited, unrestricted access to the system. A mistyped command can cause serious damage, for that reason it is recommended that you log on as a regular user whenever possible.
Once you have logged on, you can end your session by typing [exit]. This will log you off the system.
Linux differentiates between root users and regular users by changing the console prompt. If you are logged on as a regular user the console prompt will display the [$] symbol. When logged on as root, the [#] symbol is presented.
If you are logging on using Telnet, you may notice that Linux will not allow you to directly log on as root. This is a security measure, and a can be bypassed by logging on as a regular user, and switching to root. Once you have logged on, enter [su -] at the console. You will be prompted for the root password, and then authenticated as root. Note the following regarding the Switch User command:
- If you do not include the dash (-), you will only inherit the context of root, not the environment.
- To switch back to your own account, type [exit], not su again. Switching back to your own account will mean you have logged on as you switched to root switched to you, essentially 3 consoles.
- You can switch to any user on the system.
Tip – If you did not create any users when you installed Linux, you can quickly create a user named joe, with default settings, by typing [useradd joe] at any console prompt. You will not be able to log on as joe until you set a password on the account. Do this by typing [passwd joe] and entering a password.