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RMAN configuration for backup & recovery with Oracle RAC ( 10gR2, 11gR1, 11gR2)

RMAN configuration for backup & recovery with Oracle RAC ( 10gR2, 11gR1, 11gR2)

Oracle RAC database like a single database needs a backup & recovery strategy to protect against media failure. Oracle RAC architecture has shared control files, data files, redo logs and spfile (recommended). Archive logs that are generated by each RAC instance thread are either in a local file system on each node or on a shared storage (ASM, CFS, NFS). The existence of archive logs generated by instances’ threads and their type of location (shared or non-shared among all instances) determines the specifics for Oracle RAC backup and recovery.

In a single instance database an instance can access all data files and the backup and archive log destination. While performing backup the backup location is accessible. While performing a restore or recovery the backup location and the archive location are also available.

There are two most common Oracle RAC configurations

  1. Shared Oracle ASM, CFS or NFS for data files and archive logs and backups in FRA. All components are shared by all instances. Each instance can perform backup and restore/recovery.
  2. Local archive NFS mounted to all other cluster nodes. The accessibility of the backup location from the RAC instance determines how backup and restore take place. That is what determines which instance can perform backup and restore.

For Oracle RAC and FRA setup make sure that both DB_RECOVERY_DEST and DB_RECOVERY_DEST_SIZE have same values across all cluster instances.

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July 8, 2011 Posted by | oracle | 15 Comments