This fact is often overlooked, but it's very important when you are planning your build. With ZFS, you either have to buy all storage you expect to need upfront, or you will be wasting a few hard drives on redundancy you don't need. The key issue is that expanding capacity with ZFS is more expensive compared to legacy RAID solutions.
But there is a caveat with ZFS that people should be aware of.Īlthough ZFS is free software, implementing ZFS is not free. Many home NAS builders consider using ZFS for their file system. RAIDZ expansion (most requested ZFS feature ever?) is coming, courtesy of Sneak preview at OpenZFS DevSummit!- OpenZFS October 19, 2017 Please note that RAIDZ expansion is under development. The bad news is that adding drives to an existing vdev may accrue some overhead, but the good news is that this overhead can be recovered. I have written a blogpost about this new feature.
It will probably be available somewhere around August 2022. It seems that RAIDZ expansion is now being worked on.
