IBM AIX HACMP SG24-5131-00, Hardware User Manual

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Cluster Planning
47
The above example screen will add a Notification Method to the ODM, so that
upon appearance of the HPS_FAULT9_ER entry in the error log, the error
notification daemon will trigger the execution of the
/usr/sbin/cluster/utilities/clstop -grsy
command, which shuts HACMP down
gracefully with takeover. In this way, the switch failure is acted upon as a
node failure.
2.6.2.2 Notification
The method that is triggered upon the appearance of a specified error log
entry will be run by the error notification daemon with the command
sh -c
<en_method>
. Because this a regular shell, any shell script can act as a
method.
So, if you want a specific notification, such as e-mail from this event, you can
define a script that sends e-mail and then issues the appropriate commands.
Alternatively, you can always customize any cluster event to enable a Notify
Command whenever this event is triggered through the SMIT screen for
customizing events.
2.6.2.3 Application Failure
Even application failures can cause an event to happen, if you have
configured this correctly. To do so, you have to find some method to decide
whether an application has failed. This can be as easy as looking for a
specific process, or much more complex, depending on the application. If you
issue an Operator Message through the
errlogger <message>
command, you can act on that as you would on an error notification as
described in 2.6.2.1, “Single Point-of-Failure Hardware Component
Recovery” on page 46.
Because the Notification Method is an object in the node’s ODM, it has to
be added to each and every node potentially facing a situation where it
would be wise to act upon the appearance of an error log entry.
This is NOT handled by the HACMP synchronization facility. You have to
take care of this manually.
Note