Some people mention ZFS send feature, which should prevent sending unchanged blocks. You could use rsnapshot to a different machine (that needs to be just a lit

Some people mention ZFS send feature, which should prevent sending unchanged blocks. You could use rsnapshot to a different machine (that needs to be just a little bit larger than the original one) and personally I would recommend borg backup, which can deduplicate, compress and encrypt and isn't hard to setup. This could result in the backups being a fraction of the original - depending on the data. You can use AWS S3/ DO Spaces which is a lot cheaper or other compatible interfaces using rclone serve sftp + sshfs with borg or in the case of restic or duplicacy natively. You can also lookup tarsnap, rsync.net and others for remote backups. In home scenarios, you usually care about documents, pictures a few specific videos and some music above everything else. This tends to be a fraction of the total capacity. The rest doesn't change very often and is not such a loss but tends to be quite huge in comparison. So to backup all documents and pictures one or two external drives and/ or a cloud backup is sufficient. Personally, for some important documents I use orgpad.com which I help build. I am personally responsible for the infrastructure - so the backups actually have at least three tiers, independent providers etc. That is just a side effect of having a SaaS platform with a reasonable and contactable team behind it.