Recommendation - Two 3-Drive (Raid-Z1) or One 6-Drive (Raid-Z2)

[FreeNAS4Ever]

Hello,

I'm building my first NAS and will be running FreeNAS 11. This will be a relatively small build for home use. My plan is to use six WD Red 2TB drives. I had originally thought to build my array with all six drives and use Raid-Z2. My concern with this plan is if I decide to expand the array in the future, I would have to replace all six drives with higher capacity drives in order to accomplish this. My question is would it be better for me to build two 3-drive arrays using Raid-Z1 which would give me a more cost-effective upgrade path at the cost of additional redundancy for the entire NAS? Given what I have read about the reliability of WD Red drives, I am thinking the two 3-drive array approach makes sense.

I appreciate any comments on this.

 

[danb35]

I think most of us would recommend the RAIDZ2 pool for the better redundancy. Though it would depend a bit on how important the data on the server will be.

 

[SweetAndLow]

Raid z2 is what everyone is going to tell you to do. If you want easy expansion then mirrors are the best.

 

[Chris Moore]

I just went through one of my RAIDz2 vdevs and replaced all six of the 2TB drives with 4TB drives so I know exactly the thing you are thinking of because I just did it about a month ago. It really isn't that painful if you buy one drive a month. You just have to plan ahead and budget for the cost. RAIDz2 is really the way to go. One of the servers I manage at work had three drives fail in the same vdev and it would have killed the entire storage pool if it were not for the hot spare and the fact that not all the drives failed at exactly the same time.

 

[Arwen]

Another vote for RAID-Z2, (unless you have GOOD backups, or NEED the IOPS of 2 vDevs).