On 9 December 2014 at 20:22, Tim Hamilton <[email protected]> wrote:
> If any of you had my hardware, how would you construct your storage layout?

The more disks you have, the higher the chance of having a disk failure.
The older the disks you have, the higher the chance of having a disk failure.
I like low-maintenance, high-reliability solutions where they fit
well, so I would aim for a system that uses a few, large, disks, and
plan to replace them in 2-3 years.

I'd start by trying to estimate how much storage I might want within
the next couple of years.

Let's say I want to have 2TB of storage. In that case, I'd purchase
two 2TB drives, mirror them in btrfs, done.[1]
  mkfs.btrfs -m raid1 -d raid1 /dev/disk/by-id/foo1 /dev/disk/by-id/foo2

Time goes by, the amount of data I'm collecting ramps up hugely, I
need more space.
So, I'd buy a couple of 4TB drives, and add them to the pool and then
perhaps rebalance:
  btrfs device add /dev/disk/by-id/foo3 /mnt
  btrfs device add /dev/disk/by-id/foo4 /mnt
  btrfs balance start /mnt

Later, I'd remove the original drives as they were getting old, and
probably look at replacing them with bigger drives.
  btrfs device delete /dev/disk/by-id/foo1 /mnt
  btrfs device delete /dev/disk/by-id/foo2 /mnt

Anyway, this all works, at least on the 3.17 kernels. An aside: on
much earlier ones I noticed that the free space reported by 'df' was
always quite wonky for RAID1 btrfs filesystems, but it seemed to get
fixed eventually.

Footnotes:
1: I'd actually buy three drives, with the third an externally housed
one used for off-site backup.
_______________________________________________
luv-main mailing list
[email protected]
http://lists.luv.asn.au/listinfo/luv-main

Reply via email to