I want to get a home nas running with freenas

currently I have server essentials 2012 running but the whole domain enviorment seems like overkill for what i want to accomplish. I just want to backup my three computers to the nas.

I have a mini itx system running 8gb ram, an atom processor at 1.3ghz i believe and 3 2tb wd red drives.

im new to freenas and im wondering what setup can get me the most reliability, similar to a raid5. i dont quite understand the zfs system.

also if you have other suggestions other than freenas, im open to suggestions.



You specifically mentioned FreeNAS and you have ZFS available to you. I'd use RAID-Z and you will get the advantages of ZFS. This is what I'm doing for a development test server with 3 x 3TB drives sliced up with iSCSI.

You can look over an example with some nice screenshots at Building ZFS Based Network Attached Storage Using FreeNAS 8 which is a nice reference on what you are trying to do.

RAID-Z will get you 4TB of usable space, failure protection for one drive failure, and expansion down the road as you need it.


Do create a zfs pool because Raidz (same hdd configuration as Raid5) will give you all the benefits of Raid5 and none of the downsides. Zfs will give you End to End Checksum of all your filesystem with automatic repair. It will prevent the 'silent hole' that occurs with Raid5 - which comes more likely with ever extra GiB you install.

ZFS can have its own problems but it solves the ones with raid.

That said, I subscribe to the raid greed problem.

Mirror and backup is my advice.


With two drives, it's impossible to get the mix of redundancy and capacity that RAID5 provides.

RAID5 requires 3 or more drives, with data being written to two of the drives, and a parity bit being written to the 3rd. Generally the data drives and parity bit drive change as you lay down data. The parity bit means that if you lose a drive, you can reconstruct either the data or the parity bit as needed and rebuild a lost drive.

With 2 drives, you're limited to RAID0 or RAID1. RAID0 is striping - there's no data redundancy, but you'll have 4 TB total.

RAID1 is mirroring - meaning each disk is a copy of the other, so you'll only have 2 TB capacity.

Wikipedia has a good overview of RAID levels.

  • i have 3 drives. – alexthefourth Aug 28 '13 at 2:00
  • Ah, sorry, I misread that question. So why not do a RAID5? – ernie Aug 28 '13 at 15:38

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