I've read a lot of posts on this forum by people interested in using ZFS where they would use a NAS or a home server with RAID today, and I'm sure they have the same questions I do about expansion/recovery.
I think the use case is that we want ZFS for the transactional features and because it doesn't require hardware RAID, but we should be able to do everything we can do with an infrant (netgear) readynas NV+ or a drobo... in a nutshell. I want one storage pool (mount), because I don't want to navigate through different drives/mounts to go through my movies/music/whatever. I want to at least be able to add drives later of the same size and still have one pool. I'm not sure if the other poster was talking about the infrant specifically when he said NAS, but I haven't seen another NAS or external storage device that lets me add another drive and automatically expands. Infrant calls this RAID-X, and drobo says its something proprietary in their RAID. How does expansion work with other NAS like Thecus? Drobo also lets me add drives of any size and still have one drive, but drobo can only go up to 2TB without splitting into two drives (infrant can't go past 2 TB at all yet). Another feature of drobo that infrant might not have is... if a drive fails... or if I just decide to pull the drive out while the box is running... all I need to do is place a new blank drive in and it will rebuild the pool automatically so I'm ready for another failure. how does this recovery work in ZFS? zpool create... zpool add... I can't tell from what you're saying... for instance I want to buy 2 1TB drives for a 4 or 5 bay setup. Later I want to add 1 TB at a time, until I fill the bays. It sounds like if I started with 2 drives, and then create a new stripe with only one drive... then that new stripe won't have parity... what happens if that drive fails? being able to add drives of any size like the drobo isn't essential... its nice to have... being able to pop out a drive and pop in a new one and have it automatically regenerate is something I accept I won't have in an opensoalris based system I build myself just like I know its not going to detect a drive and auto expand without me doing something in a shell... but being able to add one drive, having full parity on all drives, and seeing all the files under a single mount in the filesystem are all important. -- This messages posted from opensolaris.org
