ServerNet Cluster 6780 Operations Guide (G06.28+, H06.05+)

ServerNet Cluster Software
ServerNet Cluster 6780 Operations Guide—525606-003
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SNETMON
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Detects the presence of other systems in the ServerNet cluster and establishes the
ServerNet message-system connections.
•
Monitors and responds to events that affect the message-system connections,
such as processor failures, reloads, and path events.
•
Receives path-event information from the individual processors in the node and
translates this information into system-connection status information and EMS
events.
•
Responds to queries from OSM client applications using the Subsystem
Programmatic Interface (SPI) protocol.
•
Provides ServerNet status information to SNETMON clients.
•
Keeps its backup process up to date.
This list shows the details for the SNETMON process:
SNETMON Fault Tolerance
SNETMON is a fault-tolerant process pair. An SNETMON process pair exists on every
node in a functioning ServerNet cluster. In the event of total failure of the SNETMON
process, the $ZPM persistence manager spawns a new SNETMON.
For fault tolerance, the SNETMON process pair can be configured to run on a list of
processors. For example, in systems having eight processors, HP recommends that
you configure SNETMON to run in the following CPU list: 2, 5, 6, 3, 7, 4. Refer to the
ServerNet Cluster 6780 Planning and Installation Guide for more information.
The $ZPM persistence manager starts the primary SNETMON process on the first
processor in the list (processor 2), and the primary chooses the next processor in the
list (processor 5) to start the backup. A failure in the primary processor (processor 2)
causes a takeover. Processor 5 then becomes the primary, and a new backup
SNETMON is created in the next processor in the list (processor 6). In this way,
SNETMON can survive a variety of outages.
Abbreviation SNETMON
Description ServerNet cluster monitor process
Subsystem Name SCL
Subsystem Acronym ZSCL
Subsystem Number 218
Recommended Generic Process
Name
$ZZKRN.#ZZSCL
Process Name or Process Pair
Name
$ZZSCL
Product Number T0294
Program File Name $SYSTEM.SYSnn.SNETMON