Retention Levels and Retention mappings for Vault and Policy

[snawaz3]

What is the difference between the retention levels and retention mappings for profiles and policy? Which overrides which? I want to control image expiration through vault. I have set all my policy retention levels to 

Daily - Infinity -  Level 10,

Weekly - Infinitely - Level 5

Monthly - Infinitely - Level 8

There is no particular reason why I chose those retintion levels. But I had learned that the retention levels need to be the same for all drives to be equally utilized.

The retention levels in my profiles are

Daily - 1 week - Level 14

Weekly - 4 weeks Level 13

Monthly - 1 year - Level 12

The problem I have is when I ran my weekly half of my backup were each written to 1 tape with 1 image. As a result I now have a large amount of tapes. Could any body shed some light on this?

[Mark_Solutions]

The thing to bear in mind is not what mapping level it is (i.e. infinity) but what number it is (retention level), that is all that is important when it comes to writing to the same tapes.

So if you want to write lots of backups with a 4 week retention to the same tapes they must all be level 13 in your case

So retention level overrides everything else when it comes to writing to tape, even if the retention mapping is the same (i.e. the number of days, week, years etc.)

That  does mean that by default infinity 10, infinity 5 and infinity 8 are all different retention levels and will not go to the same tape

Hope this helps

#edited as i even confised myself!!#

[snawaz3]

Thanks. So if I have different retention levels irrespective of the retention mappings they will write to different tape. Say if I have level 13 mapped to 1 week and level 12 mapped to 1 week I will get level 13 on one tape and level 12 on another tape?

[Mark_Solutions · Accepted solution]

Yes - that is right - level 12 is different to level 13 so will go to different tapes, even though they are both set to 1 week

#edit# unless you allow multiple retentions per media in the Master Servers Host Propeties - but not usually good practice to use that

[snawaz3]

Another scenario. All my policies are set to write to disk. I use vault to duplicate to tape. I use retention levels for the different profiles I have setup eg Daily, Weekly and Monthly, Level 14, 13 and 12 respectively. All retention levels in my policies are Daily, Weekly and Monthly, Levels 10,5 and 8 respectively. Since my policies are writing to disk the retention level should not matter as I am controlling my image expiration through vault. All I need to make sure is that the retention plicies on my policies are set to infinitely irrespective of the mappimgs?

[Mark_Solutions]

The retention to disk makes no difference - it all just writes to disk

Only the tape copies (vaulted) are affected as it is "media" that has the issue and must match

[snawaz3]

Thanks a lot Mark