Understanding Retention and Storage

Support
#1

Hello,

OS: UnRaid - No VMs

I am using Appdata Backup plugin which is currently running daily and keeping up to 3 backups. Each backup folder is ~65Gbs; so, the whole backup folder is approx. 200 Gb.

I am planning on using Backblaze to store this backup folder, but I don’t want to spend crazy amount of money in cloud storage. My plan to run Duplicacy jobs:

Backup job - 3 times a week (M, W, Sat)
Prune job - Delete older than 3 days, keep 1 every 60 days if older than 180 days, and keep 1 every 30 days if older than 90 days.

Is this math correct?

  • First 3 days: 1,755 GB
  • Next 87 days: 7,020 GB
  • Next 3 months: 1,755 GB
  • Last 8 months: 2,340 GB

Total storage for the year:
1,755 GB + 7,020 GB + 1,755 GB + 2,340 GB = 12,870 GB or approximately 12.87 TB

#2

No. Duplicacy deduplicates, so If you backup your app data using duplicacy you will likely end up with less than 65 GB of data on Backblaze, regardless of number of revisions: original data will be compressed and the each additional version will take space for changes only.