I've recently been making upgrades to an old PC, so I could have my own little linux file server at home. My thought was to use a few big disks in a software raid5. Nothing too fancy, and I'll probably just use Ubuntu for simplicity. While looking at the pile of disks of data I intend to transfer over once it's finished, it occurs to me that a couple of them are actually a nice size, although just a quarter of the size of the new disks I purchased. I assume it's still true that I can't just lump the smaller disks in with the new ones in a single raid set and expect it to use all my space, but since I don't believe in a no-win scenario, I've started pondering ways to cheat the rules. Thats were the nested raid thought comes in. The idea is to create two separate raid5 sets, and then connect them as a jbod. The first raid5 set would use the size of my two smaller disks, spread across all the disks, and the second raid5 set would use the remaining space on the larger disks. I'm not especially concerned that the drives may be slightly different speeds, I know the tradeoffs.
Something like this:
Disk 1: ####################
Disk 2: ####################
Disk 3: ####################
Disk 4: #####
Disk 5: #####
Final resulting jbod:
######################################################################
With raid 5 it should be that there is enough redundancy to lose any one drive and keep trucking. Has anyone tried or considered this before, or maybe know a better way to get the results I'm after?
Edit: Considering a plan B also. It would involve 3 sets of raid 5. I little more complicated than the other plan, but both little drives could die and the whole thing would keep on going.
Something like this:
Disk 1: ####################
Disk 2: ####################
Disk 3: ####################
Disk 4: #####
Disk 5: #####
Final resulting jbod:
######################################################################
Something like this:
Disk 1: ####################
Disk 2: ####################
Disk 3: ####################
Disk 4: #####
Disk 5: #####
Final resulting jbod:
######################################################################
With raid 5 it should be that there is enough redundancy to lose any one drive and keep trucking. Has anyone tried or considered this before, or maybe know a better way to get the results I'm after?
Edit: Considering a plan B also. It would involve 3 sets of raid 5. I little more complicated than the other plan, but both little drives could die and the whole thing would keep on going.
Something like this:
Disk 1: ####################
Disk 2: ####################
Disk 3: ####################
Disk 4: #####
Disk 5: #####
Final resulting jbod:
######################################################################
Last edited: