The diag command loads the diagnostic controller and displays the Online
Diagnostic menus.
Running the Online Diagnostics in Concurrent Mode
To run Online Diagnostics in concurrent mode, use the following steps:
1. Log on to the AIX operating system as root or superuser (su).
2. Enter the diag command.
3. When the DIAGNOSTIC OPERATING INSTRUCTIONS display, follow the
instructions to check out the desired resources.
4. When testing is complete; use the 3 key to return to the DIAGNOSTIC
OPERATING INSTRUCTIONS. Then press the 3 key again to return to the AIX
operating system prompt. Be sure to vary on any resource you had varied to off.
5. Press the Ctrl-D key sequence to log off from root or superuser (su).
Maintenance Mode
Maintenance mode runs the Online Diagnostics using the customer's version of the
AIX operating system. This mode requires that all activity on the AIX operating
system be stopped so the Online Diagnostics have most of the resources available
to check. All of the system resources except the SCSI adapters, memory, processor,
and the disk drive used for paging can be checked.
Error log analysis is done in maintenance mode when you select the Problem
Determination option on the DIAGNOSTIC MODE SELECTION menu.
The shutdown -m command is used to stop all activity on the AIX operating system
and put the AIX operating system into maintenance mode. Then the diag command
is used to invoke the diagnostic controller so you can run the diagnostics. After the
diagnostic controller is loaded, follow the normal diagnostic instructions.
Running the Online Diagnostics in Maintenance Mode
To run the Online Diagnostics in maintenance mode, you must be logged on to the
customer's version of the AIX operating system as
root
or

superuser (su)

and use the
shutdown -m and diag commands. Use the following steps to run the Online
Diagnostics in maintenance mode:
1. Stop all programs except the AIX operating system (get help from the system
operator if needed).
2. Log onto the AIX operating system as
root
or

superuser (su)

.
5-12 7046 Model B50 User's Guide