Can I use 2 1tb drives as a 2tb drive and also have 2 2tb drives and create a raid5 volume from them

[Ryan_21]

Hi freenas community

Is it possible to use 2x 1tb drives as a 2tb drive and also have 2x 2tb drives as well to be all put together to create a raid 5 volume?
Is this possible?

My system specs are:
Amd a8-7600
Asus a88xm-a
16gb Corsair ram
(Currently) 2x 1tb Western Digital Red drives (Buying) 2x Hitatchi Ultrastar 7K3000 2TB (Enterprise Grade)

Thanks in advanced

Ryan

 

[Dice]

Is it possible to use 2x 1tb drives as a 2tb drive and also have 2x 2tb drives as well to be all put together to create a raid 5 volume?

Sort of, but probably not the way you expect.
The smallest drive in the vdev will determine the percieved size of drives in that vdev.
So you'll find yourself sitting with 1+1+2+2TB drives, forming a raidz1 as if you were only using 1TB drives.
On the upside, you can upgrade&replace your 1+1TB drives to 2TB drives later.

The better solution would probably be to set the 1+1 TB drives as a mirrors and then adding the new drives as a second pair of mirrors to that pool.

 

[Vito Reiter]

The short answer is no, those 1TB drives would be in a RAID-0 whether you let FreeNAS handle that or a hardware RAID card. That being said if any of those two drives failed you'd lose the data on the whole pool (Including those 2TB drives). You can set up a RaidZ1/2 with all those drives (RaidZ1 is native Raid5) You'll have the equivalent space to as if you had 4x1TB drives but you can replace the 1TB drives with 2TB in the future for more space. Basically, you may as well do a 4 Disk RAID-0 with your proposed approach. I would set up a 4 Disk Z1/2 and replace those with bigger drives from there.

 

[Dice]

The short answer is no, those 1TB drives would be in a RAID-0 whether you let FreeNAS handle that or a hardware RAID card. That being said if any of those two drives failed you'd lose the data on the whole pool (Including those 2TB drives). You can set up a RaidZ1/2 with all those drives (RaidZ1 is native Raid5) You'll have the equivalent space to as if you had 4x1TB drives but you can replace the 1TB drives with 2TB in the future for more space. Basically, you may as well do a 4 Disk RAID-0 with your proposed approach. I would set up a 4 Disk Z1/2 and replace those with bigger drives from there.

What? You do disregard mirrors as an option entirely. Which would indeed provide redundancy.

 

[Vito Reiter]

What? You do disregard mirrors as an option entirely. Which would indeed provide redundancy.

He asked to get those 2x1TB drives as a single 2TB drive... He also asked to use Raid5 (In our case RaidZ). I didn't recommend mirroring the 1TB drives because then he'd have even less space or equal space to the 4 total drives in RaidZ1. Also, if you mean mirror all 4 drives, he'd only have 2TB of usable space. I just personally think that it's one of the least efficient ways to set that up unless he wants the equivalent to RaidZ2 redundancy which is what the 4 disk mirror would technically supply when it comes to total failure threshold, but still not the case when you can't lose ANY two drives, just one in each set of mirrors. I felt I answered the question appropriately and forums are forums, nothing I, or anyone else says, is determined law unless it is a REQUIREMENT of FreeNAS.