Hardware Recommendation for new NAS and questions about running a boot drive off of USB.

[Jaz]

Hello all,

Thank you for having a look at my post!

I have a few old Mac Pro towers sitting around not doing much and I am not very happy with my storage solution and back up procedures so far, so I am hoping to build two NASs out of two of the Mac Pro towers. Here are the specs for the primary NAS in question:

• Motherboard make and model :
• --- Mac Pro 4,1
• CPU make and model :
• --- 2x Intel Xeon X5550
• RAM quantity :
• --- 128GB DDR3-1333 2Rx4 Registered ECC
• Hard drives, quantity, model numbers, and RAID configuration, including boot drives :
• --- Boot Drive: 30GB OCZ Vertex Turbo SSD
• --- Storage Drives: 6x WD Gold 16TB
• Hard disk controllers
• --- NA
• Network cards
• --- SolarFlare SFN5122F Dual Port 10Gbe PCIe Adapter

My plan is to set up a RAID Z2 on the main NAS since I feel more comfortable having a two drive redundancy.

My first question is: Should I just use 5 of the drives in the Z2 raid?

My plan is to have a lot more storage than I need right now and grow into this system over time. I want it to hold all of my data, I do photo work and it can take a lot of space. I was thinking a Z2 setup with 5 drives would let me hold onto the 6th one either as a spare to swap in any time there is a problem or use it to back up all the data I have at this present time and use it as an offsite backup that I back up onto every few months until my usage exceeds it's capacity. This set up seems the most straightforward, but also seems a little bit wasteful to just have a drive in reserve like this.

Alternatively, I was considering installing all 6 drives into the machine. This should give me more space than I should ever need, but also will allow me to have increased performance when reading data. The main problem with this is that the machine only has 6 SATA connections.

This leads me to the 2nd question: Can you use a 2.5in SSD in a USB adapter?

I have seen a lot of recommendations to not use USB drives as a boot drive. Normal USB drives seem to be designed for moving files around and storing files, but not for constant reading and writing operations. The impression I have is TrueNAS is basically constantly writing and accessing the drive and so will stress it's components and make them fail rather quickly. However, I get the impression I should be ok with to use that small SATA SSD as my boot drive because it should have provisioning and other features that are generally missing on USB drives? Will I still get those features if I use the 2.5in SSD in a USB adapter? Is this a better setup than running the disk off of native SATA inside of the tower? Also, is this drive even good to use? It is ancient, but it is small and seemed perfect for a boot drive : OCZ SSD

The 3rd question I have is: Do I need a cache drive?

The impression I have is that I don't really need a L2ARC setup. I have lots of RAM and this NAS's primary job is file storage. At the moment, I have no real plans for running PLEX or VMs on this machine, though I thought adding all this RAM would allow me to perhaps expand into something like running VMs down the road. Is there any real need to spend the money on some sort of two NVMe drive PCIe adapter to run a mirrored cache on for my use case? It largely seems like a waste of money for me, but if there is something I am missing or should consider, I would be happy to hear this feedback!

4th question: Is it ok to store a backup on a JBOD?

I have another Mac Pro tower, I was going to just shove all the spare HDDs I will free up from my desktop by moving to the NAS and run them as JBODs to store a backup of the primary NAS on. My thinking is that this lets me repurpose hardware and ideally, I should never need this back up. The primary NAS has two drive redundancy, but just in case it seems good to still have a backup on a machine that is not the primary NAS. But is it too careless to store a backup on a 5-6 drive JBOD that has no redundancy? It seems like a lot of points of failure should I ever need to use the backup.

Please excuse my inexperience on this topic, I am new to making a NAS, but this project has been interesting so far and I am really excited to have my data stored in a more backed up and redundant form.

Any feedback or suggestions will be useful and appreciated, thank you!

 

[sretalla]

Should I just use 5 of the drives in the Z2 raid?

I was thinking a Z2 setup with 5 drives would let me hold onto the 6th one either as a spare to swap in any time there is a problem or use it to back up all the data I have at this present time and use it as an offsite backup that I back up onto every few months until my usage exceeds it's capacity. This set up seems the most straightforward, but also seems a little bit wasteful to just have a drive in reserve like this.

Is having a backup a waste? I think not.
Sounds like the best plan.
Keep in mind that you'll be unable to add another drive to the VDEV once it's created... for at least another year or 2 (some later release after 13.0 comes out... when they introduce the OpenZFS version containing RAIDZ expansion... even 13.0 won't have it, so some version after that)

I was considering installing all 6 drives into the machine. This should give me more space than I should ever need, but also will allow me to have increased performance when reading data

Not sure how you're planning to measure that, but probably will not be faster.

1 VDEV of 5 or 6 drives has the same IOPS (= 1 single drive). Maybe a tiny bit more throughput, but will heavily depend on sequential read/write to show that (if at all).

Can you use a 2.5in SSD in a USB adapter?

Yes. Recommended if you must use USB.

Do I need a cache drive?

Probably not, you can always add one later (and remove it if it proves less useful than predicted). RAM is always better and L2ARC will stral RAM to store its tables, so should be used carefully.

If your working set (files you use all the time) is larger than 32GB... maybe.

Is it ok to store a backup on a JBOD?

How long are you prepared to live without a backup?

One drive failure will require you to rebuild your pool and perform a full backup again before you have any backup at all...

That could take a day or more.

If your pool has some kind of problem that requires recovery when you don't have a backup... that would be bad.

A backup of any sort is better than none, but be prepared to pay for what you're comfortable to live with.