4 ms·
> I've been in this exact situation before in a storage expansion. Can you tell us what solution that was? Something with ZFS or BTRFS? My experience with clas
by noAnswer 3y ago
> I've been in this exact situation before in a storage expansion.
Can you tell us what solution that was? Something with ZFS or BTRFS? My experience with classic RAID system is, you can't expand them without reinitializing them. (But that comes with obvious warnings about data loss.)
- wtallis 3y agoTraditional hardware RAID requires you to start over from scratch to expand an array. ZFS has some limited ability to expand an array, but there are still a lot of scenarios where the recommended solution is to start over from scratch. BTRFS has full flexibility for online resizing of arrays and changing between RAID modes and rebalancing the array, but its parity RAID modes aren't really trustworthy enough yet for a backup provider to be relying on.
- SteveNuts 3y agoNot always true, Dell PERC allows online expansion (you can even change raid levels on the fly in certain circumstances) but the controller switches from buffering writes to write-through cache policy during the operation which further slows things down.
- jnsaff2 3y agoThis may not be the answer you are looking for but one option is Ceph. Several cheap, low-power NAS boxes running Linux/Ceph and throw disk at them. Depending on the data you store you can have 3-way replication of Erasure Coding at your preferred risk/performance level. Disk failures are painless, box failures don't lose data, expansion and re-balancing scales with the number of disks and pretty quickly the limiting factor is your network (4-5 modern spinning disks can easily saturate a 10G network link).