Confused by consolidation
I'm trying to figure out the best backup strategy that works for me. Something like this:
Every day of the past month (incremental)
Every month of the past year (full)
Every year (possible? Or do I have to do this manually?)
I've read through the KB, but I'm still trying to wrap my mind around how consolidation works. If I understand correctly, if I'm using incremental and have have "Number of backups exceeds: 30", then after 30 backups the oldest backup (which is a full backup) will be re-created with the second oldest backup (which is an incremental), to create a new full backup. This process will continue every time the backup is run, so as not to exceed 30 backups. Is this correct?
My second question is, if I set "Storage period of old backups exceeds 30 days" does this mean if I don't backup for 30 days, my next backup will delete all my other backups?
Your comments and advice would be greatly appreciated :)
Thanks for the help, Pat. Just a few clarifications:
You could do an incremental task, creating a new full after 13 incrementals, you would get a new full every 2 weeks and your incremental chains would not be too long.
You would then keep the 24 most recent chains (to make it one year, since you have 2 chains per month)
Wouldn't this keep daily incrementals beyond the past month, thus taking up a lot of space?
If you have one full, you don't backup for 30 days, and then you create a new backup, the new backup will be created (at this point there is nothing to consolidate), then the following one will be created and the previous one will be consolidated (because the older backup is more than 30 days old and there is one backup to consolidate).
So if I do 30 days worth of incremental backups, then do no backups for a month, then resume backups, those previous 30 versions will be deleted?
Geoff,
Yes, the scheme I proposed creates a lot of incremental backups that will stay around.
You could consider creating 2 tasks.
- one incremental task, do a new full after 6 incrementals, keep only 4 chains (that would be your last month backup, with a daily backup),
- one full task, do a new full every month.
Of course, it is not ideal, since you would get "duplicate" fulls (one from the daily backups, one from the monthly backups).
I used this scheme for a while in fact (the double backup), but then after a few years of backing up, I realize I don't need to keep system backups more than a few months, and I came back to a simple chain, single task.