i have a doubt regarding MRP process.
How MRP process knows that "this is the archive log with sequence no ###### is needed to apply)?
whether it reads control file? and if it reads standby control files then how the standby controlfile is updated with archive log information to be applied to DR?
i searched through the net but did not get any clear answer.
The controlfile keeps the information of archive log. When ever and log swicth occur and it is archived, the sequence number of the same is updated in the controlfile.
when you create standby controlfile of primary controlfile, the same is present on the standby controlfile.
When you implement the FRA then the LOG_ARCHIVE_FORMAT is ignored and archive files are generated in OMF form. Since, at standby FRA is not implemented files will be generated as per LOG_ARCHIVE_FORMAT only and MRP process will be able to apply the archived log file on standby. Even if FRA is implemented at both sides then also archive name generated at primary & standby are different and MRP is able to apply archives.
MRP searches for logs that are registered in standby controlfile, independently of LOG_ARCHIVE_FORMAT. LOG_ARCHIVE_FORMAT is used only for manual recovery.
thanks,,....but i am still confused..
who detects the GAP and HOW ?????
"For a physical standby database, Oracle introduced a request-response system for gap resolution through the FAL background process. The FAL method of gap resolution is initiated by the Managed Recovery Process (MRP). If the MRP detects a gap in archived redo logs during the application of log files, it requests the archiver process of the primary database to resend the archived redo log files which have caused the gap sequence.
- There are two important parameters required for gap resolution through the FAL background process: fal_server and fal_client. These two parameters need to be set in the initialization parameter file of the physical standby database. fal_server is the service name of the primary database and fal_client is the service name of the standby database. ""
is this correct???
thanks once again
I like it
What problem are you trying to solve? It's great you want to know how things work, but what exactly does this give you. If I had several questions like this I would try to take Oracle's Data Guard class and ask them there.
For a physical standby database , Oracle9i Relase 2 introduction a request-esrponse system for gar resolution through the FAL background process. The FAL method of gap resolution is initiated by the Managed Recovery Process MRP. If the MRP detects a gap in arcived redo logs during the application of log files, it request the archiver process of the primary database to resend the archived redo log files which have caused the gap sequence .There are two important parameters required for gap resolution through the FAL background process: fal_serve and fal_clinet.
These two parameters need to be set in then initialization parameter file of teh prysical standby database. The fal_clinet sholud be one of the remote archival destinations of the primary database pointing to this standby database. When MRP detects a gap sequence, it requests then archiver process of the primary database.