Missing RMAN Duplexed location
Steven Cowlayshaw, July 26, 2018 - 12:32 pm UTC
Thanks very much for your response Connor.
I fully understand what you have said in your update. However, I would consider there would be to much risk in using the RMAN Duplexing feature, as if one or more locations are unavailable you DO NOT get a backup at all.
What I would like to know is why this feature was not coded in a way which would still write to all available locations if one or more locations are unavailable, so at least you get a backup. Maybe this was more difficult to code and/or would degrade performance, I do not know, this is what I would like to know. Maybe the Oracle RMAN Designers/Developers could answer it. That would be the best outcome.
As an example what is the better scenario from the following:
1. One of the Duplexed destinations is unavailable, the backup job fails entirely, therefore no backup available for restore and recovery, RMAN reports the issue of the unavailable destination which can then be resolved.
2. One of the Duplexed destinations is unavailable, the backup job succeeds to the available destination/s, therefore a backup is available for restore and recovery, RMAN reports the issue of the unavailable destination which can then be resolved.
I would say scenario 2 above is the better one. Therefore I would like to know why scenario 2 was not considered appropriate?
As you say, scripting could be used to check the disk locations before RMAN starts. Then modify the RMAN statement based on what is available at runtime.
I am also experimenting with using something like the following to run immediately after the main backup in my script:
BACKUP BACKUPSET ALL Format <new location> ;
Thanks in advance
Steve
July 27, 2018 - 1:15 am UTC
I agree - I'd like to see an extension along the lines of (say):
RMAN> configure duplex destinations 3
RMAN> configure duplex minimum successful 2
or something similar to that.
All I can suggest is to log this at
https://community.oracle.com/community/database/database-ideas and encourage the community to vote on it