What's the best way to expand my storage?

[TrentMcDougall]

Hey guys!

I'm pretty new to FreeNAS so go easy! I currently have a N54L Microserver that has two 2TB drives in mirror and 2x4TB of RAM. I also have the 256GB drive that came with it which is in a separate pool and is only used for temporary files such as downloads and drop folder sharing around the house. My freeness build is FreeNAS-9.2.1.5-RELEASE-x64 (80c1d35). I'm at about 90% capacity and its filling up fast!

I'm still a student so money is relatively tight. I will only be able to buy RAM or storage once every few months. So my question is, what is the best way to expand my storage while still maintaining redundancy?

Eventually I would like 4x4TB drives so I was thinking of buying one 4TB drive and adding it to the 2x2TB pool. Will this work? How would I set up the RAID?

I'm assuming that 8GB of RAM won't be enough if I add more storage, correct?

Any help will be appreciated!

 

[BigDave]

Trent, this is going easy on you believe me.
Read the stickies on this forum, read the manual.
There's quite a steep learning curve if your data is
important to you.

 

[TrentMcDougall]

Hi Dave,

Having done some reading, I still haven't quite found the answer to my question. Everything I've read talks about using the same sized drives. If thats the case, does that mean I can't add the 4TB drive into the mirror? Does this consequently mean I can't ever get to my desired 4x4TB config without first buying two 4TB drives at once, then transferring the data from the 2x2TB pool to one of the drives? Is it even possible to have a RAID config of 2x2TB + 1x4TB that is stable/reliable? Is changing the raid type possible without at some point wiping all the drives? Will that mean I have to buy even more drives to transfer my data to while I change the raid type?

As you can see I'm still quite confused about this. As you said the learning curve is steep. From what I've read I know what I'd do if I had enough money but with parts coming in dribs and drabs, I haven't been able to find out whether my stop-gap solution is viable and if not what a better way to go about it would be.

 

[cyberjock]

You know if you read my presentation I do multiple examples. And one of my examples is almost identical to what you are proposing.... ;)

 

[TrentMcDougall]

Ah cool! guess I missed that one! I'll have a read now

 

[TrentMcDougall]

Ok so from what I understand, I have the following options that immediately give me more storage but still give me redundancy on all my disks:

1. Buy one HDD, wipe the disks and create a new RAIDZ1 vddv.
   • This would provide redundancy for all three disks
   • It's the cheapest option
   • But I would have to do the same again to add the fourth disk.
   • Also "RAIDZ1 is dead"
2. Buy two HDDs, wipe the disks and create a new RAIDz2 vdev.
   1. This way I can slowly swap out disks until all 4 have 4TB
   2. At the end of the day I'll have 8TB capacity
      
   3. And any two disks can fail without losing data
   4. But this is slower than RAIDZ1 and mirroring
   5. And I have to upgrade all 4 disks to see any capacity increases
3. Buy two HDDs and add them to the same pool as a second mirrored vdev.
   1. I don't have have to wipe any disks
   2. I can swap out disks till until all 4 have 4TB
   3. I only need to upgrade two disks to get a capacity increase
   4. At the end of the day I'll have 8TB capacity
   5. Two disks can fail without losing data so long as they aren't in the same vdev
   6. It's faster than the first two options

Is this correct? Have I missed anything?

From this, the third option seems the best but what are the disadvantages? Slightly higher risk of failure? Also is the third option essentially RAID 10?

 

[Ericloewe]

Option number three is essentially RAID 10, yes.

Do not worry about performance. RAIDZ2 on modern hardware will have no problem saturating GbE with file sharing workloads.