To use the operating system, your system must be running and you must be logged in. When you log in to the operating system, you identify yourself to the system and allow the system to set up your environment.
For more detailed information about logging in or off your system, see Starting the System in AIX Version 4.3 Quick Beginnings.
This section describes the following procedures:
You need to start a session on your system before beginning to work on your system. After your system is turned on, just log in to the system to start a session.
Your system may be set up so that you can only log in during certain hours of the day and on certain days of the week. If you attempt to log in at a time other than the time allowed, your access will be denied. Your system administrator can verify what your login times are.
You log in at the login prompt. When you log in to the operating system, you are automatically placed into your home directory (also called your login directory).
If an error requiring attention occurs, a three-digit code remains, and the system unit stops. Consult your system administrator or refer to the AIX Version 4.3 Problem Solving Guide and Reference for more information about error codes and recovery.
When the self-tests complete successfully, a login prompt similar to the following appears on your screen:
login:
If the login prompt does not display, see your system administrator, or go to the steps in "Problem Determination" in the AIX Version 4.3 Problem Solving Guide and Reference.
login: LoginNameFor example, if your login name is denise:
login: denise
password: [your password]
If the password prompt does not appear, you have no password defined; you can begin working in the operating system.
After you have logged in, depending on how your operating system is set up, your system will start up in a command line interface (shell) or a graphical interface (for example, AIXwindows or AIX Common Desktop Environment).
You can have more than one concurrent login. You do this by using the same login name or by using different login names to log in to your system. This can be useful if you are working on more than one project and want to maintain separate accounts.
Note: Each system has a maximum number of login names that can be active at any given time. This number is determined by your license agreement and varies among installations.
For example, if your other login name is denise2, at the prompt, enter:
login denise2
If the password: prompt appears, enter your password. (The screen does not display your password as you type it in.)
You now have two logins running on your system.
See the login command in the AIX Version 4.3 Commands Reference for the exact syntax.
The su (switch user) command enables you to change the user ID associated with a session, if you know that user's login name.
For example, if you want to switch and become user joyce, at the prompt enter:
su joyce
If the password: prompt appears, enter joyce's password. If you don't know the password, the request is denied.
To verify that your user ID is joyce, use the id command. For more information on the id command, see Displaying User IDs.
See the su command in the AIX Version 4.3 Commands Reference for the exact syntax.
After a successful login, the login command displays the message of the day, the date and time of the last successful and unsuccessful login attempts for this user, and the total number of unsuccessful login attempts for this user since the last change of authentication information (usually a password). These messages are suppressed if there is a .hushlogin file in your home directory.
At the prompt in your home directory, enter:
touch .hushlogin
The touch command creates the empty file named .hushlogin if it doesn't exist.
The next time you log in, all login messages will be suppressed. You can instruct the system to retain the message of the day, while suppressing other login messages.
See the touch command in the AIX Version 4.3 Commands Reference for the exact syntax.
At the prompt, do one of the following:
Press the end-of-file control key-sequence (Ctrl-D keys).
After you log off, the system displays the login: prompt.
See the logout command in the AIX Version 4.3 Commands Reference for the exact syntax.
Attention: Do not turn off the system. Turning off the system ends all processes running on the system. If other users are working on the system, or if jobs are running in the background, data may be lost. Perform proper shutdown procedures before you stop the system.
If you have root user authority, you can use the shutdown command to stop the system. Do not turn off the power to your system without using the shutdown command. This can result in lost data. If you are not authorized to use the shutdown command, simply log off the operating system and leave it running. For detailed information about shutting down or rebooting your system, see "Shutting Down" in AIX Version 4.3 Quick Beginnings.
shutdown
When the shutdown command completes and the operating system stops running, you receive the following message:
....Shutdown completed....
See the shutdown command in the AIX Version 4.3 Commands Reference for the exact syntax.
Commands and Processes Overview
User Environment and System Information
Customizing the User Environment