Setting up Local -> NAS-A -> NAS-B -> Cloud (B2)

Hi there - new Duplicacy user here! I have a couple questions on getting things setup the ideal way. My intent is mostly to backup a bunch of data on Site A Synology to Site B Synology via SFTP, then copy from Site B Synology to B2. However, I also have one or two computers in Site A which I would like to backup to storage on Site A NAS and let it then go from A to B and B2. I know how to do this part:

  • On local computers, setup repos to be backed up and add NAS-A as SFTP storage to each computer
  • On NAS-A, setup repos for its data and add NAS-B as SFTP storage
  • I’ve setup the web GUI on the local computers and both NAS

What I need to figure out is how to setup the copy of local computer data from NAS-A storage to NAS-B storage and the copy from NAS-B storage to B2. From the forum topics like Encryption and backup/copy to same storage and Duplicacy copy confusion/question on this, it sounds like I need to setup dummy repos

  1. On NAS-A, initialize a dummy repo using a local path to A’s storage area as a default storage, then add the SFTP storage on NAS-B and do a copy from the dummy repo
  2. On NAS-B, initialize a dummy repo using a local path to B’s storage area as a default storage, then add B2 as a second storage and copy from the dummy repo

I’m trying to make sure I’m getting the process correct so I bolded all the duplicacy verbs. So basically the:

  1. local computers backup to NAS-A, then NAS-A copies to NAS-B
  2. NAS-A backs up its own data to NAS-B as well. Is this deduped with the copies from the local computers?
  3. NAS-B copies all its storage to B2.
  4. Somewhere, I need to prune NAS-A, NAS-B, and B2… I’m guessing NAS-A prunes its own storage, and NAS-B prunes its own as well as B2?

Am I getting all this correct? And then my final question is… Is there any way I can setup the dummy repo’s in the web gui? it would be nice to see the various storage usage and version graphs for my three storage locations (NAS-A, NAS-B, and B2).


If these data also exit on the local computers, then the answer is yes. However, you don’t expect the deduplication to work if the data on NAS-A are backups of data on the local computers.

This is right but you need to makes sure that pruning on different stoarges must be synced, otherwise backups pruned from the destination storage would be copied again from the source storage.

You don’t need to setup the dummy repos’s in the web gui. Under the hood the web gui does it for you. You just need to add storages one by one and they will be included in the graphs.

As far as I’ve understood, you don’t need to install Duplicacy on both NAS in the case one of them will be storage only. Only when you want to do backups from one of them (in your case, NAS-A), you have to install it.
You could also share the directories you want to backup on NAS-A to one of your local computers and do the backup from the latter one. (I’m a newbie, too, so this part could be wrong …)