RAC Attack - Oracle Cluster Database at Home/Database Backups
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RAC Backups and Recovery (e)
- Setup Backups
- Flashback Database
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- Archived Logs
- Database Backups
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We will configure backups to take full advantage of the cluster by running in parallel.
- Configure the RMAN default channels and parallelism. RMAN> configure device type disk parallelism 2 backup type to compressed backupset; RMAN> configure channel 1 device type disk connect 'sys/racattack@rac1'; RMAN> configure channel 2 device type disk connect 'sys/racattack@rac2'; RMAN> show all;
- Take a complete hot backup of the entire database. RMAN> backup database plus archivelog; Starting backup at 04-MAY-09 current log archived channel ORA_DISK_1: starting compressed archived log backup set channel ORA_DISK_2: starting compressed archived log backup set ... Finished backup at 04-MAY-09 Starting backup at 04-MAY-09 channel ORA_DISK_1: starting compressed full datafile backup set channel ORA_DISK_2: starting compressed full datafile backup set ... Finished backup at 04-MAY-09 Starting backup at 04-MAY-09 current log archived channel ORA_DISK_1: starting compressed archived log backup set channel ORA_DISK_2: starting compressed archived log backup set ... Finished backup at 04-MAY-09
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Crosscheck the backup. What happens and why?
RMAN> list backupset summary;
Key TY LV S Device Type Completion Time #Pieces #Copies Compressed
------- -- -- - ----------- --------------- ------- ------- ----------
1 B A A DISK 04-MAY-09 1 1 YES
2 B A A DISK 04-MAY-09 1 1 YES
3 B A A DISK 04-MAY-09 1 1 YES
4 B A A DISK 04-MAY-09 1 1 YES
5 B F A DISK 04-MAY-09 1 1 YES
6 B F A DISK 04-MAY-09 1 1 YES
7 B F A DISK 04-MAY-09 1 1 YES
8 B F A DISK 04-MAY-09 1 1 YES
9 B A A DISK 04-MAY-09 1 1 YES
10 B A A DISK 04-MAY-09 1 1 YES
RMAN> allocate channel for maintenance device type disk;
released channel: ORA_DISK_1
released channel: ORA_DISK_2
allocated channel: ORA_MAINT_DISK_1
channel ORA_MAINT_DISK_1: SID=111 instance=RAC1 device type=DISK
RMAN> crosscheck backup;
RMAN> list backupset summary;
Try this again, without allocating the maintenance channel. What happens and why?