Implementing Data Guard - Expert Consolidation in Oracle Database 12c - page 360

Protection Mode: MaxAvailability
Databases:
CDBFSDCB - Primary database
CDBFSDCA - Physical standby database
Properties:
FastStartFailoverThreshold = '30'
OperationTimeout = '30'
TraceLevel = 'USER'
FastStartFailoverLagLimit = '30'
CommunicationTimeout = '180'
ObserverReconnect = '0'
FastStartFailoverAutoReinstate = 'TRUE'
FastStartFailoverPmyShutdown = 'TRUE'
BystandersFollowRoleChange = 'ALL'
ObserverOverride = 'FALSE'
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS
Fast Start Failover (FSFO) is disabled as you can see. As a prerequisite to enabling FSFO you will need the primary
and the target standby database to have Flashback Database enabled. Ideally the other databases in the configuration
have flashback enabled as well, but this is not mandatory. It is possible to configure FSFO with a configuration
using maximum performance—or asynchronous redo shipping—but that is not recommended for the risk of data
loss. If you trust software to perform the failover operation then you would want to be in a position where no data
loss is expected. The previously suggested maximum availability configuration is used in this example, and the
Oracle documentation claims that it will ensure there is no data loss. In situations where you have multiple standby
databases you need to define which standby database you would like the Observer to fail over to, and it can only fail
over to that one database. Setting the database property “FastStartFailoverTarget” on the primary database triggers
the Broker to update all other databases in the configuration. It needs to be set only if you have more than one standby
database. Another parameter you need to set is the Fast Start Failover Threshold. This parameter which measures the
maximum duration in seconds during which neither the standby nor the Observer have connectivity with the primary
database. Automatic failover will be initiated by the Observer if no communication is possible with the primary for
more than FastStartFailoverThreshold seconds. During the process the primary will shut down by default. As part of
the failover procedure, the failed primary database is automatically reinstated by the Broker once it is entering mount
state unless you configure it not to.
With the default configuration parameters in place you can enable FSFO, connected as SYS to the primary
database:
DGMGRL> ENABLE FAST_START FAILOVER;
Enabled.
DGMGRL> show configuration
Configuration - fsconfig
Protection Mode: MaxAvailability
Databases:
CDBFSDCB - Primary database
Warning: ORA-16819: fast-start failover observer not started