6 Drive ZRaid1 config/setup

[JIsabelle218]

Hello all,
I'm and inquiring about a new setup I have built. I have 6 drives usable, and hopeing to configure in two vdevs under one volume. First vdev would consist of 3 x 3tb WD Red Drives. Second vdev would consist of 3 x 2tb WD Red Drives (That's what I had on hand). Both vdevs would be ZRaid1 so effectively I could loose 1 drive out of each vdev and be fine. I also do regular backups to offsite. My wuestion is how to set this up. Do I need all six drives installed to get the ball rolling or can this be completed with the 3 x 2tb and add the second vdev at a later date?
Using 9.2.1.6 release

Thank you for the help.

 

[indy]

You can add vdevs at a later date.

However raidz1 is not the best choice for important data.
I think some people here have lost their pool during rebuild.
Best read up on it and make an informed choice.

 

[JIsabelle218]

Indy,
Thanks for the reply. Conversely to my setup with 6 drives (3 x 2tb and 3 x 3tb) would a valuable alternative be a Raidz2? My only issue with this option and correct me if I'm wrong, is that I'd be loosing the top 1gb of my 3 x 3tb drives. Also later down the road for expansion purposes if I wanted to up the capacity of the volume I would have to swap all of the drives. Versus in the 2 vdev scenario, I could do 1 vdev at a time....Any ideas or thoughts are appreciated.

 

[Ericloewe]

Well, in the near future you could upgrade the 2TB drives to 4TB (for instance), yielding some 12TB vs the initial 8TB. Later, you can then upgrade the rest of the drives to match the 4TB ones.

 

[JIsabelle218]

Eric,
Just to clarify,
Your example would be in the 2 vdev setup correct.
I think I'm leaning toward that, since I perform regular backups and redundancy off site.

In regards to setup.
I would just perform a normal Raidz1 with the 3 2TB drives I have, the add another vdev later and expand the volume?

 

[indy]

Eric is suggesting a 6 disk raidz2.
When you run out of space you can first swap out the 2TB disks for 4TB disks and in a second step later the 3TB disks.
Each step yielding an additional 4TB.