Can we use different size/brand HDDs with FreeNAS?

[Deyken]

Hi Guys,

I am an absolute noob to NAS. With recently upgrading my internet service to an unshaped/uncapped business account, I have had sweet internet speeds and as a result took absolute advantage of that. Result: full hard drives.

Over the past few months I added a new HDD here and there and had since built a nice collection of different brands (Seagate, WD, Maxtor etc.) and of different sizes (250GB, 500GB, 1TB, 2TB and 3TB units). Having read through many online tutorials of how to set up FreeNAS, I am definitely leaning towards taking this approach to effectively consolidate all my media, data and other backups. I own and run a software and graphic design company, so much of the important data (code backups, vector graphics etc.) also get stored on my many different HDDs.

Leading to my question: As I understand with RAID, essentially taking 2 or more HDDs, each of the same type/brand/capacity makes an array of those HDDs at the smallest one's capacity. One or two crashes, data still in tact. I also understand that if you like to live on the edge, you can rather stripe all the HDDs, which essentially lobs all your sets of capacity together for one nice big pool of data. One or more HDDs crash, you go back to the stone age.

So, my question: I would classify myself as an "edge" kinda guy, so I am going to stripe a bunch of drives lying around at home. Since not a single one belongs to a distinct brand, age or capacity, can I add all these puppies into an existing machine I have sitting around (a former media center pc), stripe them and carry on with life, or do they all need to belong to a distinct brand, capacity?

Looking forward to your answers and assistance!

 

[danb35]

You can freely mix brands, speeds, and capacities of disks. As long as your media center PC meets the system requirements (specifically, at least 8 GB of RAM), you can do what you're proposing, with the caveat (which you seem to recognize) that it will be very risky to your data--if a single disk fails, you lose all the data on the pool.

Although you can do what you're suggesting, ZFS is designed from the ground up to ensure data integrity. Creating a non-redundant pool like you're proposing defeats one of the main purposes of the ZFS filesystem.

 

[Deyken]

You can freely mix brands, speeds, and capacities of disks. As long as your media center PC meets the system requirements (specifically, at least 8 GB of RAM), you can do what you're proposing, with the caveat (which you seem to recognize) that it will be very risky to your data--if a single disk fails, you lose all the data on the pool.

Although you can do what you're suggesting, ZFS is designed from the ground up to ensure data integrity. Creating a non-redundant pool like you're proposing defeats one of the main purposes of the ZFS filesystem.

Hi danb35,

Thank you very much for clearing that up for me. So, if I did decide to go the safer route and stick with the ZFS file system, how would I go about setting my NAS up? Would I need to pick a HDD (perhaps my newest WD Green 3TB), purchase another one or two like that and set up the NAS as a RAID? Thus, total NAS capacity 3TB.

Maybe I should build yet a second NAS with no redundancy, just so I don't end up wasting all those other HDDs... Or, can I set up 2 different sets of HDDs in a single box, one RAID and the other striped?

PS: Where I am, they have just released WD 6TB units. Will FreeNAS be able to work with these?

 

[danb35]

I don't have any experience with the 6TB drives, but I believe I've seen other folks here using them. I can't think of any reason they shouldn't work.

If you haven't already, I'd encourage you to read through cyberjock's presentation here: http://forums.freenas.org/index.php...ning-vdev-zpool-zil-and-l2arc-for-noobs.7775/ It'll cover a lot of how ZFS works when it comes to building your pools, because that's something you really want to get right from the beginning--it's hard to fix mistakes made early on.

For redundant arrays, you have two basic options: mirrors and RAIDZ. If you wanted 3TB of net capacity in your array, one way (probably the simplest way) to accomplish that is with a mirror of 2x 3TB disks (and your WD green would work fine, but check into using the WDIDLE3 utility to set the park time to something sane). If either disk fails, the other has your data. Another way to accomplish that would be with 4x 1TB disks in a RAIDZ1 array, or 5x 1TB disks in a RAIDZ2 array. These will give you one and two disks of redundancy, respectively. With drive capacities as they are, RAIDZ1 isn't recommended much any more, though I'm sure plenty of people still use it.