Backup retention duration

Support
1

Hi,

I’ve configured my backup strategy retention as following:

7D:1h,3W:1D,3M:1W,2Y:1M,3Y:1Y

Can someone explain to me what this exactly means so I can check if I have it done the right way?

2

It’s saying:

  • For the most recent 7 days, keep at most 1 backup per hour
  • Beyond that, for the most recent 3 weeks, keep at most 1 backup per day
  • Beyond that, for the most recent 3 months, keep at most 1 backup per week
  • Beyond that, for the most recent 2 years, keep at most 1 backup per month
  • Beyond that, for the most recent 3 years, keep at most 1 backup per year
  • Do not keep any backups after 3 years
3

Thanks! Would you say this is a good policy?

4

How often do you have your backups scheduled to run? If every hour, I would change the first pair from “7D:1h” to “7D:U”. This will keep all backups during that 7 day window. It may sound like there’s no difference, but Duplicati is unforgiving in its time windows. If two backups ran with end times slightly less than an hour apart, it will delete one of them. So setting your policy to “7D:U” is a way to achieve the result you’re probably looking for. (Again, this is assuming you are running backups hourly. If you are running them every 4 or 8 hours then it probably won’t matter.)

Other than that, it looks good assuming you don’t want to keep backups beyond 3 years.

5

Thx! I changed it to: 7D:1h,3W:1D,3M:1W,2Y:1M,5Y:1Y

1 Like
6

Hi,

1D:U,3M:1W
Does this mean that I keep every backup for 1 day (runned hourly) and from then on a weekly one for 3 months and everything after 3 months is being deleted?

7

Yes, if that’s the entirety of your retention policy then your summary is correct.