You can't create a backup in the FRA, when the FRA runs out of space. This doesn't make much sense if both the archivelogs and the backups are stored in the FRA. The most common solution is to create a backup of the archivelogs, which will also delete these archivelogs. RMAN's crosscheck command will resolve the inconsistency between the FRA usage in the database and on disk.īe aware that the most common problem with an undersized FRA is a database hang, because the database cannot create an archivelog file at time of a logswitch. The first backup is removed, and the reclaimable space is back to 0. Do not create any cleanup script and let the database handle itĪ common RMAN script for archivelog files is:Īlter a "Delete obsolete" in RMAN.Two common ways to delete archivelogs are: It is a protection files are not deleted if it conflicts with the policy. The deletion policy itself does not delete archivelog files. CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY.CONFIGURE ARCHIVELOG DELETION POLICY TO SHIPPED TO ALL STANDBY.CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO SBT.If you do create an archivelog deletion policy, they can be deleted after you meet the requirements in the policy. Or the logs are obsolete according to the backup retention policy. You can define your archivelog deletion policy in RMAN. If there is no archived redo log deletion policy in RMAN, the files can be deleted when backed up at least once to disk or SBT. You do not need 3500 GB for each instance. So, in this case, you would use a maximum of 3500 GB on the +RECO disk group for the database. You can check the configuration by looking at two parameters. How much archivelog do you want to keep on disk?.How do you want to use flashback database?. How long do you need to keep your backups?.Flash Recovery Area needsīefore you start configuring your FRA sizing, you need to define your own needs for the recovery windows and retention time. The FRA size is set with only one parameter for all file types together, but we can do some calculations on the size needed for individual file types. Main file types are archivelog, flashback log, backups, as well as mirrors for your control files and redo log files.Īll files in the FRA are Oracle-managed files. Using a Flash Recovery Area simplifies the administration of your database by automatically retaining them for as long as they are needed for restore and recovery activities, and deleting them when they are no longer needed, because the space is needed for another backup and recovery-related purpose. SQL> flashback database to restore point CLEAN_DB Ĭompare the SCN# from step 9 above to the reference SCN#.In the Oracle database, the Flash Recovery Area or FRA is a location on disk where the database can create and manage several kinds of backup and recovery-related files.SQL> select current_scn from v$database.Also, note down the SCN# for reference and we will refer to it as "reference SCN#"įlashback to the guaranteed restore point Now, in order to restore your database to the guaranteed restore point, follow the steps below: Verify the information about the newly created restore point. Where CLEAN_DB is the name given to the guaranteed restore point. SQL> create restore point CLEAN_DB guarantee flashback database.If step 3 shows that ARCHIVELOG is not enabled then continue else skip to step 8 below. The database must be in ARCHIVELOG modeĬreate a guaranteed restore point: After you have created or migrated a fresh database, first thing to do is to create a guaranteed restore point so you can flashback to it each time before you start a new workload.Must have created a flash recovery area.The user must have the SYSDBA system privileges.Guaranteed Restore point: Prerequisites: Creating a guaranteed restore point requires the following prerequisites: NOTE: In this article Flashback logging was not turned ON. it is always available (assuming you have enough space in the flash recovery area). The difference between the two is that guaranteed restore point allows you to flashback to the restore point regardless of the DB_FLASHBACK_RETENTION_TARGET initialization parameter i.e. One can create either a normal restore point or a guaranteed restore point. Restore point: Restore point is nothing but a name associated with a timestamp or an SCN of the database. More specifically, this article describes steps on how to use the ‘guaranteed restore points’. This article describes how to use Oracle’s flashback feature to quickly restore a database to a state that existed just before running the workload. One way to ensure a clean database is to recreate the entire database before each test run, but depending on the size of it, this approach may be very time consuming or inefficient. Often while conducting benchmarking tests, it is required to load a clean database before the start of a new run.
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