building a low power NAS

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sdadept

Limp Gawd
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I need a NAS for backing up my home and 2 small business servers (primary and failover). The machines are virtual (100 to 200gb per machine) and I plan to do specific directory backups nightly and full VM backups every weekend. Will write offsite backups monthly.

To make this thing last over a long period of time and so I don't kill my power bill with it, I want to try and go low power on the NAS unit. Anyone have recommendations for either a canned unit to buy for this or ways I could put this together from scratch? I'm thinking of using FreeNAS.

Initially I plan to use 4 2tb wd drives in raid 5.
 
Hmm can I ask what your power range is? Since you will only be running at night it won't be to bad.. My 18 disk 16x WD 1gig green and 2x 160 RE2 drives + a phenom II 940 only take 160w at idle and at load around 230w <- measured by my battery. Thats also with a hardware raid card. How many weeks do you want to store as well and whats the max size you want out of this thing?
 
How much storage and performance do you need? If your needs are slight I would use FreeNAS on an Atom-based box with 4 disks in RAID5, but performance won't be fantastic and you can't easily expand it. Otherwise I would go Celeron and do the same, that $200 Intel box looks very intriguing, but again is limited to 4 disks.
 
Will this only be on for backups or will it also be used for 24/7 file serving duties?
 
Just for backups, I plan to let backups accumulate and delete them as space is needed. The offsite backups are the failsafe (I hope at least). I was thinking 8tb just so I have room for future growth. I would ideally like to put this together and have it last me the next several years without having to worry about it too much.

I've been reading around on various nas boxes and the TS-410u and TS419u boxes seem fairly appealing.

One other thing I forgot to note, even though these are in my basement now, I eventually want to co-locate so the unit ideally should be a 1u or 2u.
 
I'm getting ready to pull the trigger on a ts-419u and add 4x2tb wd drives to it. Anyone have this unit?
 
Not that particular one, but I've worked with other Qnap gear and it's good stuff. In RAID5 I doubt it can come close to saturating GigE (the charts on their web page for it make it look like it gets about 25MB/s writes and 50MB/s reads), but otherwise it should work well. You can build something for less money that will perform better, but it'll require more work and use more power (does that matter if you colo it?).
 
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That's great information keenan, thanks. The power issue doesn't matter for co-lo, only for as long as it's here at the house.

When you say I could build it for cheaper, I've been trying to price things out and I'm not completely sure. The thing that seems to be the big cost breaker is a hardware base raid controller and the mboard/proc. Any ideas on that? I'm not opposed to building something at all, in the end I just really want something that will last.
 
Well I dunno about doing a NAS but if your wanting a hardware raid controller and such a little linux would solve most of your problems instead of a nas. Whats your budget for a machine? 1500? Does it have to be rack mountable?
 
sdadept said:
When you say I could build it for cheaper, I've been trying to price things out and I'm not completely sure. The thing that seems to be the big cost breaker is a hardware base raid controller and the mboard/proc. Any ideas on that? I'm not opposed to building something at all, in the end I just really want something that will last.
Click to expand...

If you're not opposed to the idea of software RAID, something like FreeNAS, OpenFiler, or just learning Linux softraid (it's not that difficult) works fine. This is what the Qnap box does, just with underpowered hardware to get good performance, and of course the slick web interface.

You can get a nice Supermicro 1U barebones with 4 hot-swap cages, toss in a dual-core Celeron, a gig or two of cheap ECC RAM and a small IDE DoM to boot from. Throw on FreeNAS or Debian and you should be able to do 100MB/s in RAID5 without any trouble. That setup would run you probably a little less than the Qnap, but similar. If you sacrifice the nice hot-swap server-grade hardware though you can probably do it in 2U for under $400, still with quality components. And if you go the Debian route you can pretty much run whatever services you want on it, and maintaining it when its at colo should be more secure and easier.

That said, the Qnap gear is nice, and it's a simple solution. Plug in disks, turn it on, and it just works. If you don't want to spend time assembling the server, learing your NAS distro or how to use Linux softraid and whatnot, it's probably a better choice. It's not like you're going to be doing 100MB/s or probably even 10MB/s out of your colo...
 
My budget for this is to try and keep it under 1.5k.

If I do a barebones supermicro with 4 hot swap bays, is there a way I could make it diskless? I'd really like to boot from memory some how. Only way I know to do that I put a usb drive on it or something.

the primary thing stopping from buying that canned solution is that I worry about throughput
 
I was in the same situation this past summer. I was looking into the QNAP 8 bay solutions and I really couldn't justify the cost before drives.

I ended up buying an ECS 945GCT-D (Intel Atom), with a Highpoint 4320 SAS raid + gigabit NIC. All parts included, before drives was ~$600. Runs great, more than enough performance for a NAS, certainly more than a lot of the pre-built options. The only downside is that the 4320 is limited on the motherboard to PCI-Ex1, but that hasn't proven a bottleneck when transferring files over my local lan.

I've got 5RE2 drives in Raid 5 + 1 74GB gen 1 raptor and under load my KillAWatt reads 60-70w, 40w idle. The real power hog in the system is the 4320. Costs me about $5-6/month to run 24/7.
 
sdadept said:
My budget for this is to try and keep it under 1.5k.

If I do a barebones supermicro with 4 hot swap bays, is there a way I could make it diskless? I'd really like to boot from memory some how. Only way I know to do that I put a usb drive on it or something.

the primary thing stopping from buying that canned solution is that I worry about throughput
Click to expand...

As mentioned above...get a DOM...Disk on Module.

Something like this: http://www.memorydepot.com/ssd_diskonmodule.asp

I don't know anything about that particular retailer...was just the first hit on google.
 
MemoryDepot is good, I've used them a few times and been pleased with their services and those InnoDisk modules are good. The EDC8000 are quite a bit faster.
 
I learn something here every time. I had never heard of a disk on module, that's awesome.

So it looks like cost wise the two might be close, so the last thing I'm coming up against is throughput. The QNAP solution maxes @ 25mb per second it would seem. As this is going to be a backup solution, I really am hoping for more than that. If I do a raid 5 solution with 4 sata disks, should I expect more than 25mb per second?
 
Phixzet said:
Does it end up being one 6TB partition?

Can Windows (Clients) see it fine?
Click to expand...

I have WHS on the server, so it shows as 8TB minus the 20GB for the system partition. Windows, Linux and Mac clients have worked perfectly with it.
 
sdadept said:
If I do a raid 5 solution with 4 sata disks, should I expect more than 25mb per second?
Click to expand...

Well if you're using a true hardware RAID controller, yes you should be expecting more than 25MB/s. However since the QNap is more than likely using a sort of fakeRAID or hardware assisted software RAID controller, 25MB/s seems about right.
 
sdadept said:
So it looks like cost wise the two might be close, so the last thing I'm coming up against is throughput. The QNAP solution maxes @ 25mb per second it would seem. As this is going to be a backup solution, I really am hoping for more than that. If I do a raid 5 solution with 4 sata disks, should I expect more than 25mb per second?
Click to expand...

If you do a hardware RAID or proper software RAID setup you should easily get in the 200MB/s range, possibly more depending on your disks and setup. That's more than enough to fill a GigE link, and about the fastest you can expect without getting into elaborate measures to improve network performance further (SAN or 10GbE).

As mentioned the Qnap uses an underpowered processor that can't do the parity calculation fast enough to keep up those rates, and given the low read speed probably doesn't have enough I/O bandwidth available in the system either. Going to commodity hardware will shatter those limits.

Do you really have this much network bandwidth available at your colo and at your office? That'd be pretty sweet ;).
 
I have enough bandwidth over the networks to saturate this from multiple endpoints. I think I am going to go the route of building my own. I first need to figure out the best hardware raid card on the cheap. I'm looking at some of the rocketraid cards for $300ish.
 
building your own is probably the best choice. I personally have a freenas box with 2 storage arrays and I love it. One array is an iscsi target to connect to my esxi 3.5 server so I can store my vms and another array for my data. Both arrays are using a software raid 1 and read write speeds aren't to bad either. But, so that I can saturate my gig network, I will be doing a new build that will include a hardware raid card and a fairly large rackmount case to fit a decent amount of drives in. Be sure to pick up a couple gig nics too if you have a gig switch or plan on upgrading soon
 
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