Here we go! First build

[the_jest]

Well, I've been reading as much as I can, and I think I'm at the point where I have something not too crazy. Please feel free to correct me on this!

As discussed recently, this is for a home NAS functioning basically as a home fileserver, with little expectation of multiple concurrent users, transcoding, etc. However, I might run a small webserver in a jail off it as well, and will use it for Transmission, something like OwnCloud, etc. I did want a Mini ITX form factor; there's probably some overkill here but I hope I didn't go too nuts. So:

Case: SilverStone Technology Mini-ITX NAS Computer Case, Black (DS380B)

Motherboard: ASRock Rack Motherboard C236 WSI

CPU: Intel 3.70 GHz Core i3-6100 3M Cache Processor (BX80662I36100)

Memory: CRUCIAL TECHNOLOGY 16GBx2 32GB Kit, DDR4 2133 MT/s DIMM 288 (CT2K16G4DFD8213)
(sorry, that's the wrong link, to a non-ECC version. I got this: http://www.crucial.com/usa/en/ct16g4wfd8213)

Boot drive: SanDisk Ultra Fit 32GB USB 3.0 Flash Drive x 2

HDD: WD Red 4TB NAS Hard Disk Drive x 4, for a RAIDZ2 setup

PSU: Seasonic 360W 80PLUS Gold ATX12V Power Supply SSR-360GP

Silly question, as I've only ever built simple desktops before: Will I need to get SATA cables, or any other cables/small bits/screws that would be a PITA to get at the last minute when I realize I've forgotten it? What else am I forgetting?

Thanks for all input.

 

[Ericloewe]

Looks reasonable.

PSU: Seasonic 360W 80PLUS Gold ATX12V Power Supply SSR-360GP

The G-450 is much less of a pain to work with, since it has semi-modular cables.

Silly question, as I've only ever built simple desktops before: Will I need to get SATA cables

Yeah, it's best to get right-sized SATA cables.

or any other cables/small bits/screws that would be a PITA to get at the last minute when I realize I've forgotten it?

Additional fans, if applicable. Otherwise, not really.

 

[Dice]

Agree.
Looks okay.

 

[Pitfrr]

Nice build.
But regarding the number of hard drives, why 4? Do you have other spare hard drives available?

Why I'm asking? I find that when building a RAIDz2 volume, 6 drives is a sweet spot (regarding raw space versus available space) or I even would say minimun.
Considering your motherboard (it has 8 SATA ports if I'm not wrong) I'd go directly for 7 or 8 drives! ;-) (keep one SATA port for a boot device eventually)

Well don't get me wrong: it will work fine with 4 drives. Just keep in mind also that you can't add drives to an existing volume later on.

And the drawback: the more drive you get, the more drive you'll need for the backups! ;-)
And I'm not forgetting the budget that will explode accordingly.

 

[the_jest]

To be honest, it already feels like three drives more than I need!

Four 4TB drives in RAIDZ2 should give me enough space for several years. Six would be vastly more than necessary, unless of course I got smaller ones, and there doesn't seem to be any really strong reason for this. I mean, I guess 6 2TB drives would be very slightly cheaper than 4 4TB drives, and provide the same usable storage, but then I'd have six drives to upgrade one-by-one if I need to have more space.

If I'm misunderstanding the possible benefits, by all means let me know, but it sounds like more effort with little reward.

 

[Ericloewe]

That's basically it. It's just that you can double your storage for 50% more disks. But, if you're sure you don't need more, there's no reason to spend more.

 

[Robert Trevellyan]

Four 4TB drives in RAIDZ2 should give me enough space for several years.

If you only need 8TB of raw storage, at least consider the possibility of mirrors. There are tradeoffs, but you gain a lot of flexibility.

 

[Pitfrr]

You're right, I wouldn't go for smaller drives so if it is enough for you then it's fine, I just wanted to point it out.

In that case consider mirroring as Robert mentioned.

 

[the_jest]

Thanks for this suggestion. This is probably no longer the correct forum, but since we're here.... I've been reading up on mirrors and I have to confess that I'm not exactly sure what you're recommending. A four-disk mirror (I don't fully understand this topology)? Two vdevs, each a two-disk mirror? In this situation, a failure of both disks in one vdev would nuke the whole pool, yes?

The possibility of expanding the pool by getting a mere two disks is a tempting one, though.

And yes, I do keep backups on a separate device.

 

[Robert Trevellyan]

Two vdevs, each a two-disk mirror?

Correct ... unless you start with two 8TB disks.

In this situation, a failure of both disks in one vdev would nuke the whole pool, yes?

Yes, this is one of the tradeoffs. You can expect a mirror to resilver more rapidly than any RAIDZ layout, which somewhat mitigates the risk. Also, the number of vdevs directly affects the chances of a 2nd drive failure destroying the pool. Assuming 2-way mirrors:
1 vdev = 100%
2 vdevs = 33.33%
3 vdevs = 20%
etc.

The possibility of expanding the pool by getting a mere two disks is a tempting one, though.

Yes, it is.

 

[Pitfrr]

I'm not sure but doesn't a mirror offer better iops compared to a RAID volume?

I don't know if this would make a difference for your usage anyway.

 

[Robert Trevellyan]

doesn't a mirror offer better iops compared to a RAID volume?

It isn't quite that simple. The main determining factor for IOPS is number of vdevs, where more vdevs = more IOPS. It's easier to build more vdevs if each one is only 2 or 3 disks each.

For typical home users, it won't make a measurable difference, but for some workloads it's vitally important, e.g. block storage for virtual machines.

 

[Pitfrr]

Thanks...
I didn't dig much into iops performances since it wasn't a priority for my build
But I'm always interested in understanding things like that. ;-)

 

[CraigD]

RAIDz2 is as fast as the slowest disk in the vdev, any two drives can fail your data survives. Mirrors are as fast as the slowest disk in each mirror added together, however only one disk in each mirror can fail, if both drives fail in the same mirror you data is gone.

If you don't need the speed RAIDz2 is superior, it will still max out a network connection, and ANY two drives can fail without data loss.

A 4TB 5 drive RAIDz2 will give you just under 10TB of usable space (4 4TB drives will not give you 8TBs of usable space you desire)

Have Fun
PS Have you considered an ECC build?

 

[the_jest]

Sorry, I did go with ECC memory, I had the wrong link before; I've edited the original post.

A 4TB 5 drive RAIDz2 will give you just under 10TB of usable space (4 4TB drives will not give you 8TBs of usable space you desire)

I don't need 8TB space; someone else said that upthread. 6TB will do for me for the reasonable future, which is provided by 4 x 4TB drives. But again, the notion of adding capacity by adding two disks, instead of upgrading five, is an attractive prospect of a mirror layout.

 

[Robert Trevellyan]

8TB of raw storage

I wrote that based on your consideration of 4x 4TB RAIDZ2 pool layout. Emphasis on "raw storage".

 

[machasm]

Is the PSU the correct physical size? I note the case supports SFX form factors only?

 

[the_jest]

Is the PSU the correct physical size? I note the case supports SFX form factors only?

Oh, god, you're right--I didn't even look at that. Aargh. Luckily it hadn't shipped yet, so I was able to cancel it.

There aren't that many discussions of SFX power supplies here; if anyone has thoughts about whether the Corsair or the Silverstone would be the better choice, please let me know!

 

[Ericloewe]

Corsair. It's decent overall.

 

[machasm]

Either are good on the PSU front but corsair provide a 7 year warranty and I have had fairly good results with them in the past.