ZFS Copy-on-write raw image backups confusion

[Maniac]

A bit of a thread necro, but I created a tool do what @rwilms described via a TrueNAS custom app:

TrueNAS: Tool to Mount Images for ZFS RAW Copy on Write

I recently setup UrBackup on a TrueNAS custom app to allow for ZFS RAW Copy on Write image backups (the stock app doesn’t give ZFS access). One issue I found is there was no easy way to mount images. It is not supported via the UI. However, it is possible to mount the images via iscsi, but the snapshots must be cloned and the extents must be created manually. I created a docker image to do just this. The code and instructions can be found here, as well as an example docker-compose.yml. You do n…