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Best Practices for Oracle 11g Backup and Recovery using RMAN and Dell EqualLogic Snapshots
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• EqualLogic snapshots efficiently met the point-in-time recovery objectives. The Snapshot
restore operation was almost instantaneous and the entire recovery process was able to be
manually completed within six minutes.
• Restore/recovery time when using EqualLogic snapshots did not change based on the amount
of database transactions that need to be replayed, as it would if using Oracle FLASHBACK
DATABASE.
7.3 Comparison of backup and recovery methods
Key conclusions based on our test results:
• Oracle’s RMAN tool provides a powerful and efficient way to perform backup and recovery
operations. RMAN also causes a significant impact on production database server CPU
utilization for the entire duration of backup processing.
• EqualLogic snapshots can be used in conjunction with RMAN to offload the entire backup
operation to a dedicated backup server, thereby eliminating the CPU utilization impact on the
production database server.
• When using EqualLogic snapshots you can drastically reduce the time to complete point-in-
time recovery as compared to using the Oracle FLASHBACK DATABASE.
Table 4 compares RMAN full backup, incremental backup and EqualLogic snapshot based backup.
Table 4 – Comparison of backup methods
Method
DB server
impact
Backup Window
Time
RTO Impact
RPO Impact
RMAN Full
Backup
High
Depends on size
of DB and server
workload
Depends on size and
frequency of backup
and size of redo log
history
Optimizing RPO
amplifies performance
impacts on production
DB caused by RMAN
processing
RMAN
Incremental
Backup
High
Depends on size
of DB, server
workload and
transaction
history
Depends on size and
frequency of backups,
and redo log history.
Usually faster than full
backup.
RMAN Backup
Offload using
EqualLogic
snapshots
Low
Eliminates
backup time
window impact
on production
DB servers
Depends on size and
frequency of backup
and redo log history
Backup offload allows
you to optimize RPO
with minimal impact
on production DB
systems