[jeffbee]

Yes, you can use iscsi. I used iscsi initiator on macOS to make time machine backups on an exported volume from an opensolaris zfs tank. Worked fine for many years, although I no longer use that approach.

You have to install iscsi initiator on the Mac, since macOS doesn’t come with it.

[atombender]

Isn't that a block-level protocol? My server has a bunch of XFS volumes, which macOS does not understand.

[jeffbee]

Yeah it’s not really for sharing files around, but it fits the use cases of time machine.

[atombender]

Right, that's a different use than mine.