IBM Enterprise Server H80 Series - Manual (Page 120)

Note: Pressing the F3 key (from a defined terminal) produces a Confirm Exit menu
which offers two options: continuing with the shutdown by pressing the F3
key; or returning to diagnostics by pressing Enter.
For undefined terminals, pressing 99 produces a full-screen menu which
offers two options: continuing with the shutdown by pressing 99 and then
Enter; or returning to diagnostics by pressing Enter.
Concurrent Mode
Use concurrent mode to run Online Diagnostics on some of the system resources
while the system is running normal activity.
Because the system is running in normal operation, the following resources cannot
be tested in concurrent mode:
SCSI adapters connected to paging devices
Disk drive used for paging
Some display adapters and graphics related devices
Memory (tested during POST)
Processor (tested during POST)
Three levels of testing exist in concurrent mode:
The share-test level tests a resource while the resource is being shared by
programs running in the normal operation. This testing is mostly limited to normal
commands that test for the presence of a device or adapter.
The sub-test level tests a portion of a resource while the remaining part of the
resource is being used in normal operation. For example, this test could test one
port of a multiport device while the other ports are being used in normal
operation.
The full-test level requires the device not be assigned to or used by any other
operation. This level of testing on a disk drive might require the use of the
varyoff command. The diagnostics display menus to allow you to vary off the
needed resource.
Error-log analysis is done in concurrent mode when you select the Problem
Determination option on the DIAGNOSTIC MODE SELECTION menu.
To run the Online Diagnostics in concurrent mode, you must be logged on to the AIX
operating system and have proper authority to issue the commands (if help is
needed, see the system operator).
104 RS/6000 Enterprise Server Model H80 Series User's Guide