In this mode, the primary database is protected against data loss and divergence. See Section 3. You can specify a nondefault directory for the archived redo logs. See Section B. If integer minutes go by without receiving another log to process, managed recovery automatically terminates.
NOWAIT indicates that log apply services should not wait for the redo apply operation to complete before returning control to the user. By default, the recovery process will finish processing the log it is currently working on before terminating. The managed recovery operation waits the specified number of minutes before applying the archived redo logs. The managed recovery operation terminates at the end of the current archived redo log that is being processed. The NODELAY option bypasses the specified delay interval and causes the archived redo logs to be applied to the standby database without delay.
A parallel recovery uses the child processes to spread the workload of the recovery across several processes. A managed recovery in FINISH mode first applies all available archived redo logs and then continues to recover available standby redo logs, while a recovery that is not in FINISH mode only applies the archived redo logs.
Specifying the FINISH option causes the standby database to be up-to-date with the last committed transaction on the primary database. The FINISH option can be used when starting a managed recovery or when altering the mode of an ongoing managed recovery. The only thing we can do is to give the correct location for the redo log files.
Rename the redo log to the correct location:. The standby database has been activated and is now a primary database. Oracle has created the redo logs at the location specified. Note: all previous backups of this database are now invalid and cannot be used to restore this database.
The SCN number of the database is not reset. Now is a good time to make a new backup of your database! We work with partners around the world to give you the best advice and world-class local support. Find out about our continuous database protection for yourself and see how you can keep your world in motion.
Blogs Activating the standby database - performing a failover Learn more on activating the standby database to become the primary database, also referred to as a failover. September 26, Automatic Failover Automatic failover is where the software determines when the standby database should be activated to become the new primary database. What happens during activation? Create all necessary directories for trace files etc.
This can be similar set up to your primary database server as names of both the database will be same. We started the auxiliary instance with just the 3 parameters required Once we start the script RMAN will be connecting to both Target Primary and Auxiliary Standby database to perform the duplicate. RMAN will use the contents of the spfile used in the Primary database to start the auxiliary database. The set commands specified in the RMAN duplicate script will introduce new parameters to the auxiliary instance if not present in the primary instance and override any parameters with the new values if the parameters already exists in the primary instance.
Note that I have allocated equal number of channels for both target channels and auxiliary channels. This is an RMAN active duplicate feature enhancement introduced in Oracle version 12c and above to off load processing of duplicate operation to the auxiliary site. When the number of auxiliary channels are allocated equal to the number of target channels, the backup request is initiated by auxiliary channels and processing load is done in the auxiliary instance.
This is called as pull-based method of active duplication which differs from the push-based method of duplication which uses image copies of the target DB to be copied to auxiliary using target channels and is done by target instance. To know in detail about push bases and pull based method, please check here.
We can start the activity by calling the script in nohup mode as we are not sure how long the script will run and we don't any disconnects to disrupt our activity. Once the script has completed execution the database will be in mount state and recovered until the logs are available. The last step is to enable MRP process which will then keep the standby database in sync with primary database by applying the logs as and when it receives the logs.
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