In the spirit of the question LVM mirroring VS RAID1 I thought I'd push a bit further.
Suppose I have 4 identical hard drives (e.g. 1TB) that I want in a RAID setup for a backup/media server. LVM over the top seems to be current best practice for resizing, but what about the RAID layout? My options seem to be:
- 2x 1TB RAID1 sets with LVM concatenation
- 2x 1TB RAID1 sets with LVM striping
- 1x 2TB RAID10 (striped 2x 1TB) set with LVM on top
- 1x 2TB RAID6 (striped 2x1TB with 2x 1TB parity) with LVM on top
RAID-on-LVM sounds too crazy to be worth investigating, but I'd be interested if someone can make a good case for using it.
How does each of these perform in the scenario of
- The I/O load will be a combination of low but constant (e.g. video streaming) and high but bursty (e.g. a backup system)
- It is very likely that a drive will die unexpectedly
I want to upgrade (increase the capacity of) the drives 1 or 2 at a time(no longer relevant)
- At some point in the future I might want to add another 2x HDDs in RAID1 to the LVM
What are you recommendations/experiences with any of these RAID configs?