This feature provides support for double parity protection for write-once files in an Oracle Automatic Storage Management (Oracle ASM) Flex Disk Group.
With this feature you can use double parity protection for write-once files in a Oracle ASM Flex Disk Group. Double parity protection provides greater protection against multiple hardware failures. A previous release of Oracle ASM provided for simple parity protection for write-once files in a Flex Disk Group. Write-once files include files such as database backup sets and archive logs. The benefit of parity protection as compared to conventional mirroring is that it reduces storage overhead, but with a slight increase of risk of data loss after an event involving multiple hardware failures.