FreeNAS low power build with ZFS

[tknd]

I've been using FreeBSD with ZFS on older hardware (Athlon64 939 board) and it worked fine but I never liked the size of the machine, the power consumption, and forced into managing my own FreeBSD system. But the ZFS aspect was a success. It is very easy to build ZFS pools and manage them.

So FreeNAS came out with an update that added ZFS support and here came my opportunity to rebuild the machine. Here's my report of my progress so far with it.

The hardware I chose:

1. ZOTAC IONITX-A-U Atom N330
2. A-Data 2GB DDR2-800 (single stick, don't care about dual channel)
3. 2x Western Digital 2TB Green WD20EADS (migrated from my previous system)
4. APEX MI-100 Mini-ITX case
5. 4GB Patriot Razzo USB Key (for OS and booting)

The case came with a PSU. I took that out since the weight was unnecessary and the board I purchased comes with on-board power. I'm not so big on the "silence" aspect so I put the fan on the heatsink. Because of this when I placed the hard drive into the external 3.5" bay, the fan would block the SATA and power connections on the hard drive. This is not fixable without drilling holes because they only provide 2 holes for hard disk mounting. Instead I mounted the disk at an angle so that the connections would clear the fan, however, this may make the 5.25" bay unusable by a full size DVD drive. I didn't care since I don't plan on having a DVD drive in there. But it was a slight inconvenience so I'm not sure I recommend this case.

This was my first time experimenting with migrating a ZFS pool from one machine to another and it worked. One thing to note is that the ZFS version is the same on both systems so I haven't tried moving a ZFS pool from an older ZFS to a newer ZFS. In order to migrate you just have to make sure you run the "zpool export" command on the pool you will be migrating. On the new machine you then use the "zpool import" command to get the new system to recognize and utilize the pool.

My main goals in the build were low idle power and that the box was small/light enough to move around easily. I think I accomplished that. The results from the power meter at the wall are:

19-20w idle (no disks)
27w idle with disks (2x WD Green idle, but still spinning)

So that's about 20w with the system only on USB with no disks and about 4w per a WD Green drive.

The size of the box is about the size of a athletic shoe box. It isn't the best design for what I want (mini-itx board with 3.5" bays) but it works for now. I may investigate building a custom case suited for my needs. I would prefer 4 3.5" disk bays and no PSU or an externally mounted PSU since the board already comes with a PSU.

The system isn't completely silent. I did try running without the fan for 10 to 15 minutes and the BIOS hardware monitor reported 49c temperature without heavy loading. When the fan was attached it dropped to 25c (ambient temp was about 19c). So I figure it was worth it to run the fan since the hard drives aren't silent anyway. I need to investigate if the BIOS will let me lower the RPM on the fan.

The FreeNAS system was able to detect the hardware I needed it to detect correctly. Gigabit ethernet works. SATA controller works (BIOS defaults to IDE/SATA mode, but you can switch it to AHCI mode). I didn't investigate getting the wireless card working since I don't really plan on using it. But I did not see it listed in the network interfaces setup.

The Razzo USB stick with FreeNAS installed takes about 3 minutes to boot. I wish this was faster.

The system can run completely headless (no monitor, no keyboard). You can power off the system simply by pushing the power button and FreeNAS does cut off power to the system. My older FreeBSD wouldn't power off automatically during shutdown.

Hard drive spin down does work with minimal hassle. You can configure it from the FreeNAS web interface.

My recommendations if you want to do something similar:

The Atom 330 (dual core) is a little overkill. I haven't used much except ZFS and samba but the cpu utilization is always at 0. I might have to try a few things to see if it can really get loaded.

The board comes with a mini-pci express slot so there isn't much expansion opportunities. ZFS will work over USB devices but of course that's not the same speed as SATA. For that reason it might be worth it to go for the boards without the onboard with the Zotac ION ITX F-E board which does come with a full size PCI Express x16 slot but you'll have to provide your own PSU.

FreeNAS setup is pretty painless. I used an external USB CDROM to get it installed onto the USB drive. There were no issues using that method.

I went with the ION platform instead of an intel platform because it was lower power than most current intel offerings (945GC chipset, I'm looking at you!) and it had the best feature set (4 sata ports, on-board power). While the GPU is pretty useless, the HDMI connector is pretty convenient to have. But apparently intel has some new stuff in the works so maybe within a half a year, there might be decent boards to choose from as more stuff gets integrated into the CPU itself.


Overall I'm pretty satisfied. My old system was over 60w idle. The new one is less than half that and much easier to use thanks to FreeNAS and compatible hardware. I currently have the system on a 2TB mirror but there is one more SATA connector and an eSATA connector so I could expand it more in the future. It is a little pricey if you think about the total cost (about $700 for today's prices). But you do get ZFS, low power, and technically a BSD based system. FreeNAS comes with a bittorrent client so it can handle most of your file needs.

[protellect]

Thanks for the read. I'm doing something very similiar build with this:

http://www.newegg.com/Product/Product.a ... 6813182205

and a supermicro 8 port card [http://www.provantage.com/supermicro-ao ... UP918N.htm]

hoping to not just hold data, but to try out iSCSI over the two gigabit ports.