Combined with the DT_APPLICATION_STARTUP_POLICY and the presence or absence of the FORCEFLAG, Metrocluster with Continuous Access EVA handles failover scenarios in different ways when the replication mode is set to Asynchronous or Synchronous. Table 40 describes how failover scenarios are addressed in different replication modes and when the FORCEFLAG is present.
Table 40 Replication Modes and Failover Scenarios
Failover |
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Scenario | Replication Mode | DT_APPLICATION_STARTUP_POLICY | |||
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| Availability_Preferred | Data_Currency_Preferred | FORCEFLAG is present. | |
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Remote failover | Synchronous | Failover is issued immediately | Failover is issued | Failover is issued | |
during normal |
| and the package is started. | immediately and the | immediately and the | |
operations |
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| package is started. | package is started . | |
(planned |
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Asynchronous | Same behavior as in | Same behavior as in | Same behavior as in | ||
failover) | |||||
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| Synchronous mode. | Synchronous mode. | Synchronous mode. | |
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Remote failover | Synchronous | Failover is issued immediately | Failover is not issued, | Failover is issued | |
with the link |
| and the package is started. | and the package will | immediately and the | |
down |
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| not start. | package is started | |
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| Asynchronous | Same behavior as in Synchronous mode. |
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Remote failover | Synchronous | If the Merge operation | If the Merge operation | If the Merge operation | |
during merging |
| completes before the time | completes before the | completes before the | |
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| specified for the WAIT_TIME | time specified for the | time specified for the | |
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| parameter, then the package | WAIT_TIME | WAIT_TIME parameter, | |
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| is started. If not, then the | parameter, then the | then the package is | |
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| package | package is started. If | started. If not, then the | |
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| not, the package | package | |
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| There is no impact to the | ||
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| behavior when | |
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| FORCEFLAG is set or not | |
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| set. | |
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| Asynchronous | Irrespective of whether the | Same behavior as in | Failover is issued | |
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| merging operation is | Synchronous mode. | immediately and the | |
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| complete before or after the |
| package is started . | |
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| WAIT_TIME parameters, the |
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| package is started. |
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Remote failover | Synchronous | If the full copy operation is complete before the time specified for the WAIT_TIME | |||
during copying |
| parameter, then the package is started. If not, the package | |||
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| Asynchronous | Same behavior as in Synchronous mode. |
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Remote failover | Synchronous | Failover is not issued, and the package does not start. |
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during manual |
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Asynchronous | Failover is issued. | Same behavior as in | Failover is issued. | ||
suspend | |||||
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| Synchronous mode. |
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Remote failover | Asynchronous | Irrespective of whether the | If the merge operation | Failover is issued | |
during rundown |
| merging operation is | is complete before the | immediately and the | |
and link up |
| complete before or after the | time specified for the | package is started. | |
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| WAIT_TIME parameters, the | WAIT_TIME |
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| package is started. | parameter, then the |
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| package is started. If |
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| not, the package |
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Remote failover | Asynchronous | Failover is issued immediately | Failover is not issued, | Failover is issued | |
during rundown |
| and the package is started. | and the package does | immediately, and the | |
and link down |
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| not start. | package is started. | |
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490 Environment File Variables for Metrocluster Continuous Access EVA