6.1.6 Processing performed when failover occurs on ITSLM - UR
When failover occurs on ITSLM - UR, ITSLM - UR on the active server is terminated and ITSLM - UR on the standby server is started. Note that the shared disk does not contain any ITSLM - UR information that is to be inherited to the standby server.
After ITSLM - UR starts on the standby server, ITSLM - UR is connected to ITSLM - Manager. After that, ITSLM - UR starts its processing according to the business operations underway in ITSLM - Manager.
The following figure shows the processing that is performed when failover occurs on ITSLM - UR.
The following subsections explain the failover processing flows depending on the timing of the failover.
- Organization of this subsection
(1) While neither monitoring nor detection of monitored services is being performed
When failover occurs on ITSLM - UR while neither monitoring nor detection of monitored services is being performed, only connection to ITSLM - Manager is restored after ITSLM - UR is started on the standby server. Neither monitoring nor detection processing is started.
(2) While monitored services are being monitored
When failover occurs on ITSLM - UR while monitored services are being monitored, monitoring is restarted after ITSLM - UR has started on the standby server.
The following figure shows the processing flow when failover occurs on ITSLM - UR while monitored services are being monitored.
The following explains the processing flow shown in the figure, where the numbers correspond to the numbers in the figure:
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The cluster software (active server) starts ITSLM - UR (active server). The cluster software (active server) also starts periodic monitoring of server status.
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Upon receiving a notification that ITSLM - Manager has started monitoring the monitored services, ITSLM - UR (active server) starts monitoring and sends performance information.
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Because a failure has occurred on ITSLM - UR (active server), the Windows services stop.
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All Windows services for ITSLM - UR that have been registered into ITSLM - UR (active server) are stopped by the cluster software (active server) after which failover processing starts.
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The cluster software (standby server) starts ITSLM - UR (standby server). The cluster software (standby server) also starts periodic monitoring of server status.
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A notification of the start event is sent from the started ITSLM - UR (standby server) to ITSLM - Manager and transmission of performance information is restarted.
(3) While detection of monitored services is being performed
When failover occurs on ITSLM - UR while detection of monitored services is being performed, the ITSLM - Manager status changes from Detecting to Stopped. Once ITSLM - UR has started on the standby server, its connection to ITSLM - Manager is restored.
The following figure shows the processing flow when failover occurs on ITSLM - UR while monitored services are being detected.
The following explains the processing flow shown in the figure, where the numbers correspond to the numbers in the figure:
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The cluster software (active server) starts ITSLM - UR (active server). The cluster software (active server) also starts periodic monitoring of server status.
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Upon receiving a notification that ITSLM - Manager has started detecting monitored services, ITSLM - UR (active server) starts detection processing.
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Because a failure has occurred on ITSLM - UR (active server), the Windows services stop.
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All Windows services for ITSLM - UR that have been registered into ITSLM - UR (active server) are stopped by the cluster software (active server), after which failover processing starts.
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The cluster software (standby server) starts ITSLM - UR (standby server). The cluster software (standby server) also starts periodic monitoring of server status.
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A notification indicating that ITSLM - UR (standby server) has started is sent to ITSLM - Manager and connection is restored.