IBM RS/6000 SP, Maintenance Information

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MAP 0120: Supervisor Bus Problem
022 (continued)
Problem isolated to one supervisor harness: PDU-BH-J7 or PDU-BH-J8.
– Reconnect this supervisor harness at the PDU bulkhead.
– Following this supervisor harness, disconnect it from each switch assembly or processor node (each
one individually), until the frame supervisor LED #4 (top yellow LED) or LED #6 (if twin-tail) stops
FLASHING, or cable is disconnected from all processor node(s) and/or switch assemblies.
Does frame supervisor LED #4 (top yellow LED) or LED #6 (if twin-tail) stop FLASHING?
Yes No
023
– Note which processor node or switch assembly was disconnected last—this is the suspect
unit.
– Reconnect this supervisor harness to any processor node or switch assembly other than the
suspect unit.
Does frame supervisor LED #4 (top yellow LED) or LED #6 (if twin-tail) stop FLASHING?
Yes No
024
– Replace this supervisor harness: PDU-BH-P7 or PDU-BH-P8.
– Perform "Verification Test for Supervisor Bus" in
IBM RS/6000 SP: Maintenance Informa-
tion, Volume 3, Locations and Service Procedures.
Does verification test pass?
Yes No
025
– Continue with Priority 3 in table of Step 021 on page 1-22.
026
– Go to Step 041 on page 1-26
027
Problem isolated to the suspect unit noted at the beginning of Step 023.
– Go to the second bullet of Step 028.
028
– Note which processor node or switch assembly was disconnected last—this is the suspect unit.
– Reconnect supervisor harness to its appropriate processor node(s) and/or switch assemblies, except for
the suspect unit.
– Go to Step 035 on page 1-24 to continue service.
029
Communication problem with individual node or switch supervisor(s).
Attention: Powering off processor node(s) or switch assemblies in a parallel environment may cause all
jobs to flush from the queue and switch initialization to rerun.
Attention: The processor node(s) or switch assemblies must be removed from active configuration before
continuing. If processor node(s) or switch assemblies are off, continue; otherwise, ask customers to initiate
Chapter 1. Maintenance Analysis Procedures (MAPs)
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