IBM 6H0, Service Manual

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1 Key
The numeric 1 key, when pressed during POST, starts the System Management
Services (SMS) interface.
5 Key
The numeric 5 key, when pressed during POST, initiates a system boot in service mode
using the default service mode boot list.
This mode attempts to boot from the first device of each type found in the list. It does
not search for other bootable devices of that type if the first device is not bootable.
Instead, it continues to the next device type in the list. The firmware supports up to five
entries in the boot list.
The default boot sequence is:
1. Diskette
2. CD-ROM
3. Hard file
4. Tape drive (if installed)
5. Network
a. Token ring
b. Ethernet
6 Key
The numeric 6 key works like the numeric 5 key, except that firmware uses the
customized service mode bootlist that was set up using the AIX service aids.
8 Key
To enter the open firmware command line, press the numeric 8 key after the word
keyboard
displays and before the last word
speaker
displays during startup. After you
press the 8 key, the remaining POST indicators display until initialization completes.
When initialization and POST are complete, the open firmware command line (an OK
prompt) displays.
The open firmware command line should only be used by service personnel to obtain
additional debug information.
To exit from the open firmware command prompt, type
reset-all
or power off the
system and reboot.
System Unit Locations
The system consists of a minimum of two drawers in one rack: the CEC drawer and the
primary I/O drawer. These two components are connected by cables that transmit data
and control signals. An additional I/O drawer can be added if further expansion of the
system is required. The following figure shows the units.
Chapter 1. Reference Information
7