Retention question - sanity check
We have our job set up as Daily Incrementals with Monthly Active Fulls. We are changing some retention around and would like to keep 24 months of Monthly Fulls, and 6ish Months of Dailys.
Is the best plan here to just keep 180 (daily) + 18 (remaining months) for a total of 198 retention points? Or should I enable GFS Monthlys and just keep retention points at the dailies limit of 180? Also, I am not sure if enabling GFS Monthlys on an existing job has any negative effects or if it's even recommended.
Sorry this is a basic question, just looking for a little input. Thank you!
Posted Jan 7, 2021, 5:57 PM UTC
13
What sort of repository are you using? Disk, SOBR (Scale-Out Backup Repository) or a Dedup-Appliance? For Disk/SOBR you'll need at least 24x the capacity of a full backup for that, and that's not including the incrementals, which would vary according to change rate. And you'd need almost 7 months of those. Have you considered tape for your monthly backups?
Keeping 6 months of daily backups seems like overkill to me.
If you change to GFS, it will affect future backups. It won't modify any existing restore points.
That is great to know, thank you!
We are using a disk shelf with dedupe, and looks like we have a ~5% change rate with ~2x dedupe.
I remember seeing a calculator for this, but cannot find it at the moment.
Edit: Also looks like we hover between 1.6x and 2x compression which I do not remember that calculator having, unless thats multiplicative/additive with dedupe and you use that number.
If you refer to dedupe in the OS, you will see no significant gain with backups as they are compressed and already deduped. If this is however a specialized dedup appliance, the numbers look different.
The calculator is located here: https://rps.dewin.me/