I'm trying to setup a full/differential backup set. I want a full every 30 days and I want to have 2 months at any given time, 60 differentails. Seems simple till I go to figure out how to set that up. Maybe my brain is messed up.
As it runs the first time it creates a full backup let's say Jan 1. Jan 2 - Jan 31 it creates differentials. On Feb 1 it creates a new full and until March 3 it creats another 30 differentials. So now I have hit my limits on both the full and the differentials. What i thought I set up was that on March 4th it will create a new full backup while deleting the Jan 1 full backup. But wait that leaves all my differentials from Jan 2 - jan 30 essentially worthless because there's no full backup any more that would allow me to recover any date in Jan.
If I increase my full backups to 3 then my full backup on Jan 1 will stay around but the differentials will start disappearing so for the next 30 days each day another differential disappears and then the Jan 1st full backup will disappear. It's not a rolling 30 days but a kind of weird hybrid.
i guess I'd like it better if the full wouldn't disappear until the last differential it supported was removed but with the current setup that can't work. With backup space at a premium on my system I don't want to save anymore backups than I have to. If I decide that I want to have 2 months of data regardless of how many full backups I schedule and knowing that every backup that's not a full is a differential regardless of how many differentials I might create during a cycle I want 60 days of recoverable data. Maybe that means I don't use the Dynamic setup and just delete manually for now.
Going forward maybe just add a place to set the recovery period of backups be it 1 day, 1 month, 5 weeks, etc. Set the time cycle for the full backups (every "x" period of time) then calculate the max full backups to retain. Essentially the backup retention period / the total backups to retain + 1. Any differentials created between full backups are associated by the timestamp of the full being before <= to the 2nd oldest full backup. Only when a full gets deleted would the associated differentials be deleted.
As it runs the first time it creates a full backup let's say Jan 1. Jan 2 - Jan 31 it creates differentials. On Feb 1 it creates a new full and until March 3 it creats another 30 differentials. So now I have hit my limits on both the full and the differentials. What i thought I set up was that on March 4th it will create a new full backup while deleting the Jan 1 full backup. But wait that leaves all my differentials from Jan 2 - jan 30 essentially worthless because there's no full backup any more that would allow me to recover any date in Jan.
If I increase my full backups to 3 then my full backup on Jan 1 will stay around but the differentials will start disappearing so for the next 30 days each day another differential disappears and then the Jan 1st full backup will disappear. It's not a rolling 30 days but a kind of weird hybrid.
i guess I'd like it better if the full wouldn't disappear until the last differential it supported was removed but with the current setup that can't work. With backup space at a premium on my system I don't want to save anymore backups than I have to. If I decide that I want to have 2 months of data regardless of how many full backups I schedule and knowing that every backup that's not a full is a differential regardless of how many differentials I might create during a cycle I want 60 days of recoverable data. Maybe that means I don't use the Dynamic setup and just delete manually for now.
Going forward maybe just add a place to set the recovery period of backups be it 1 day, 1 month, 5 weeks, etc. Set the time cycle for the full backups (every "x" period of time) then calculate the max full backups to retain. Essentially the backup retention period / the total backups to retain + 1. Any differentials created between full backups are associated by the timestamp of the full being before <= to the 2nd oldest full backup. Only when a full gets deleted would the associated differentials be deleted.
Statistics: Posted by CityguyUSA — 30 Aug 2024, 05:48 — Replies 1 — Views 511