Chapter 5. Using the Online and Standalone Diagnostics
The diagnostics consist of Standalone Diagnostics and Online Diagnostics.
Standalone Diagnostics are packaged on removable media and must be booted
before they can be run. If booted, they have no access to the AIX Error Log or the
AIX Configuration Data.
Online Diagnostics, when installed, reside with AIX in the file system. They can be
booted:
in single user mode (referred to as

service mode

),
run in maintenance mode (referred to as

maintenance mode

)
run concurrently (referred to as

concurrent mode

) with other applications.
If the system is not booted, then the Online Diagnostics have access to the AIX Error
Log and the AIX Configuration Data.

Standalone and Online Diagnostics Operating Considerations

Note: When possible, run Online Diagnostics in Service Mode. Online Diagnostics
perform additional functions, compared to Standalone Diagnostics. This ensures that
the error state of the system is captured in NVRAM for your use in fixing the
problem. The AIX error log and certain SMIT functions are only available when
diagnostics are run from the disk drive.
Consider the following items before using the diagnostics:
When diagnostics are installed, the device support for some devices may not get
installed. If this is the case, that device does not appear in the diagnostic test
list when running disk-based diagnostics.
Support for some TTY terminals is optionally installed. If you attach a TTY
terminal to a system to run diagnostics, it may not work properly because the
AIX support for the terminal may not be installed.

Selecting a Console Display

When you run Standalone Diagnostics (and under some conditions Online
Diagnostics), you must select the console display. The diagnostics can display
instructions on any graphics display and the terminal attached to the S1 serial port.
Copyright IBM Corp. 1999 5-1