this post was submitted on 02 Jul 2024
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So this is bugging me for a while and I'm just do dumb to get how I solve this, but here's the situation:
Given I take a local backup of my system daily and have a retention policy that keeps a backup of the past 7 days each, a backup of the past 4 weeks each and a backup of the past 6 month each. That's either 17 backups or less if you consider some backups being counted as a daily and weekly or as a weekly and monthly. But that's not that important.
The interesting part is, that I also take a remote backup of my local backup daily, which has the same retention policy, so it's cascading. Here there is obviously a huge overlap of backups, but I can't wrap my head around, how I calculate this.
Is anybody willing and/or interested to solve this for and with me?

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[–] [email protected] 1 points 2 days ago

All backups are incremental, so all local backups together "count" as one full backup and all remote backups "count" as one full backup. And I take a backup of my SSD to a local HDD and from that to a hosted storage solution. I also have an old full backup on an external disk which is in my book shelf. I guess I'm pretty much fulfilling the 3:2:1 rule, right? By the way I literally counted all backups and there are 51 unique (incremental) backups,