ServerNet Cluster 6780 Operations Guide (G06.24+, H06.03+)

Troubleshooting and Replacement Procedures
ServerNet Cluster 6780 Operations Guide—525606-002
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Checking the Internal ServerNet X and Y Fabrics
HP does not recommend stopping and starting the ServerNet cluster subsystem to
repair ServerNet connectivity. The SCF STOP SUBSYS $ZZSCL command is used
primarily to ensure the orderly removal of a node from the cluster. The SCF STOP
SUBSYS $ZZSCL command normally is used prior to:
•
Physically disconnecting a node from the cluster
•
Halting the processors on a node, possibly in preparation for a system load to a
new product version of the operating system
•
Aborting the SNETMON process pair for the purpose of upgrading the SNETMON
software unless recommended otherwise by HP
Aborting and Restarting SNETMON
You can also use this sequence of commands to repair connectivity problems:
SCF ABORT PROCESS $ZZKRN.#ZZSCL
SCF START PROCESS $ZZKRN.#ZZSCL
This sequence of commands aborts the SNETMON process pair (SNETMON ceases
to exist). However, ServerNet cluster connectivity is left intact. When the SNETMON
process is started again, it queries all processors in the node to find the state of
ServerNet connections to all other nodes. If it finds any connections that are down, it
initiates a sequence to bring the connections to an online state. The outcome is
therefore similar to issuing the SCF PRIMARY PROCESS $ZZSCL command, but
there is a key difference.
The Expand-over-ServerNet line-handler processes tolerate only temporary absences
of the SNETMON process. After three minutes of absence, the Expand-over-ServerNet
line-handler processes declare the lines to other nodes to be down. Consequently, you
should abort and start SNETMON with caution. Because of the possibility of Expand-
over-ServerNet lines going down (in case the SNETMON process pair is not running
for more than three minutes), HP recommends using the SCF PRIMARY PROCESS
$ZZSCL command to repair ServerNet cluster connectivity.
Checking the Internal ServerNet X and Y Fabrics
You can use the OSM Service Connection or SCF to check the internal ServerNet
fabrics.
Using OSM to Check the Internal ServerNet Fabrics
Use the Group Connectivity ServerNet Path Test action in the OSM Service
Connection to check the internal ServerNet X and Y fabrics for the local system. Use
this test when you want to check the integrity of group-to-group connections along one
ServerNet fabric at a time. This test checks these components:
•
ServerNet cables
•
PMF CRUs
•
IOMF CRUs