Ubuntu – Recommended storage scheme for home server? (LVM/JBOD/RAID 5…)

hard drivehome-serverserverstorage

Are there any guidelines for which storage scheme(s) makes most sense for a multiple-disk home server?

I am assuming a separate boot/OS disk (so bootability is not a concern, this is for data storage only) and 4-6 storage disks of 1-2 TB each, for a total storage capacity in the range 4-12 TB.

The file system is ext4, I expect there will be only one big partition spanning all disks.

As far as I can tell, the alternatives are

individual disks

  • pros: works with any combination of disk sizes; losing a disk loses only
    the data on that disk; no need for volume management.
  • cons: data management is clumsy when logical units (like a "movies" folder)
    are larger than the capacity of any
    single drive.

JBOD span

  • pros: can merge disks of any size.
  • cons: losing a disk loses all data on all disks

LVM

  • pros: can merge disks of any size; relatively simple to add and remove disks.
  • cons: losing a disk loses all data on all disks

RAID 0

  • pros: speed
  • cons: losing one drive loses all data; disks must be same size

RAID 5

  • pros: data survives losing one disk
  • cons: gives up one disk worth of capacity; disks must be same size

RAID 6

  • pros: data survives losing two disks
  • cons: gives up two disks worth of capacity; disks must be same size

I'm primarily considering either LVM or JBOD span simply because it will let me reuse older, smaller-capacity disks when I upgrade the system. The runner-up is RAID 0 for speed.

I'm planning on having full backups to a separate system, so I expect the extra redundancy from RAID levels 5 or 6 won't be important.

Is this a fair representation of the alternatives? Are there other considerations or alternatives I have missed? And what would you recommend?

Best Answer

Like you I'm going through a rationalisation process with the disks in my home server. I too have a mix of disk sizes resulting from the organic growth of the JBOD setup I have.

I am taking the LVM route for the following reasons.

  1. Its the simplest
  2. It allows me to reuse the disks I already have in the server
  3. I have a complete backup of all the data that I am confident I can restore from
  4. I am not concerned about the recovery time in the event of a disk failure

For me the clinching factors are #3 & #4.

Related Question