On Sat, Dec 06, 2014 at 02:02:50PM +1100, Brett Pemberton wrote:
On Sat, Dec 6, 2014 at 9:16 AM, Tim Hamilton <hamilton.tim@gmail.com> wrote:
I'm in need of a PCIe SATA controller that works well under linux and supports BTRFS / ZFS raid arrays to be used in a home NAS I'm building and am no sure what I'm looking for.
My current need is only for a single additional SATA port but my preference is for a card that will support future expansion
Keep in mind, with ZFS for example, you can't do like mdadm, and just add a drive to a RAID5/6 array and reshape, growing to use more devices.
Your best bet is to start off with the maximum number of drives you plan to use, and upgrade capacities, instead of adding more devices.
remember, though, that you can always add another vdev to a ZFS pool. you can't reshape a zpool, or remove a vdev from it (and zfs doesn't have a 'rebalance' feature like btrfs) but adding a vdev works. e.g. if you have a zpool consisting of one three drive raidz vdev, you could later add another vdev of any kind (e.g. another raidz, a 2-drive mirror, etc. a vdev can even be a single disk but you get no redundancy from that - similar to raid0). a zpool is made up of one or more vdevs, which are each made up of one or more drives. you can also replace the drives in any vdev with larger capacity drives....when all drives in that vdev are replaced, the extra capacity is available for storage. craig ps: performance on a zfs pool is notably improved (especially for random writes) if you have a small (4 or 8GB is plenty) SSD partition as a zfs log device. -- craig sanders <cas@taz.net.au>