Well, if you are using a sophisticated tool like restic or borg or duplicity, the file attributes are bundled up into the encrypted chunks and all is well. How

Well, if you are using a sophisticated tool like restic or borg or duplicity, the file attributes are bundled up into the encrypted chunks and all is well. However, if you are using plain old rsync, you can use the --fake-super command line switch to maintain those attributes and I believe rsync.net customers are using that successfully. Yes, you are correct - in the old days (2001-2010 or so) we maintained a pair of "permission scripts" which allowed customers to dump all their attributes to a file and then reapply it later. Again, --fake-super seems to "fix" all of this. Generally speaking, you should always enable ZFS encryption. It improves many aspects of ZFS behavior and performance - not just space usage. Unless you have very bizarre workloads or hardware, I think that in 2020 there is no reason to not enable compression. Deduplication is another story and is very expensive to maintain - rsync.net has never run de-dupe on any systems. We (rsync.net) and I (personally) have zero experience with btrfs ...