Dell DR4300 Oracle Recovery Manager - Setting Up the DR Series System as an NF - Page 22

7 General best practices for RMAN backups to the DR Series system The Dell DR Series system supports RMAN backups over both CIFS and NFS protocols. With client side optimization drivers like Rapid CIFS and Rapid NFS backups become faster and more efficient. Several options exist with RMAN that every DBA should be aware of. These effect how RMAN behaves when performing its backup duties. Some of the most important are outlined here because they affect how RMAN will interact with a Dell DR Series deduplication appliance. Refer to Oracle's documentation for more details. Multiplexing of data is not recommended as it adversely affects the deduplication savings. Every time data gets multiplexed, the patterns may change, and the deduplication algorithm can fail to decipher the duplicates. Specify FILESPERSET = 1 when backing up to a DR Series system. FILESPERSET controls how many data files are written to a particular file within the backup set.  Backup database FILESPERSET=1 Specify MAXOPENFILES = 1 for each channel defined. This will ensure that each RMAN channel only reads from a single file at any one time. It is recommended to keep the value at minimum.  CONFIGURE CHANNEL DEVICE TYPE DISK MAXOPENFILES 1 FORMAT '/ora_df%t_s%s_s%p';  Turn on change block tracking by using below command. SQL> ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE '/oradata/rman_change_track.f';  Configure RMAN settings to backup control file and SPFILE. Auto backup on CONFIGURE CONTROLFILE AUTOBACKUP ON; Keep CONFIGURE BACKUP OPTIMIZATION OFF every time for better savings. RMAN encryption should NOT be used as the deduplication savings get affected. A listing of the global parameters can be generated by the "show all" RMAN command: RMAN> show all; RMAN configuration parameters for database with db_unique_name APPLE are: CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default CONFIGURE BACKUP OPTIMIZATION OFF; # default CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default CONFIGURE CONTROLFILE AUTOBACKUP ON; CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/mnt/apple_nfs/apple_%u_%s_%p'; CONFIGURE MAXSETSIZE TO UNLIMITED; # default CONFIGURE ENCRYPTION FOR DATABASE OFF; # default CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default 22 Setting Up the Dell™ DR Series System as an NFS or CIFS Backup Target on Oracle Recovery Manager® | April 2015