If the active sequencer or the Business Continuity Manager server on which it resides fails, the standby sequencer automatically assumes the role of the active sequencer after a specified timeout period (with a default of 5 minutes). This happens if the standby sequencer can connect to the database running on all managed Teradata systems in both data centers. If the standby sequencer cannot connect to all Teradata systems, it does not attempt to take over, in case there is only a network issue and not an actual failure of the Business Continuity Manager server.
Use the Component view in the Business Continuity Manager UI to determine which component or Business Continuity Manager server is down.
A SEQUENCER STATUS command issued on the standby sequencer displays the time remaining before the standby sequencer automatically assumes the active role. It also displays the checks performed by the standby to confirm the other Business Continuity Manager server is down.
bcmadmin> sequencer status;
HA Status : Down/Unknown
Log Replication Mode : Asynchronous
Failover Mode : Automatic
Automatic Failover Status
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Sequencer : region2_seq
Time Remaining Before Failover : 290 seconds
Failover Conditions :
Check standby sequencer can connect to all managed systems (done)
Check active sequencer has no heartbeat on all managed systems (running)
Check active sequencer has no transaction on all managed systems (running)
Individual Sequencer States
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bcm2:5344 : STANDBY (SYNCHRONIZED)
unknown host/port : DOWN
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