Josh Barratt's Blog

I recently started to really need more disk around the house. More specifically, reliable disk. Now that we’re starting to take photos of our son, and to shoot video, and do to all of this at relatively high resolution (I love our 30D in RAW, but those files aren’t small) I wanted storage and I wanted it RAID’ed.

My network at the moment consists of:

• 2 laptops
• a Mac Mini working as a media center
• an airport extreme

Very clean and simple. Currently, I have quite a few disks dangling off the back of the Mac Mini. One of them will be staying, we time machine remotely to it. The rest were being used for our media archives – both media generated by us, and media purchased by us. And they weren’t RAID’ed, which meant I wasn’t comfortable not leaving copies on my laptop(s) as well, which of course have finite drives. And since my space needs were growing rather than shrinking, this needed to change.

The options as I saw them:

• Get more external drives and some USB hubs, and use the Mac Mini to RAID attached devices
• Get a RAIDed enclosure (like a Drobo)
• Build a small server that can have a lot of disk on board, but not use much power otherwise

I went for option 3, because I wanted to use ZFS – we use it at work and I’m a big fan of it. I’m also a big fan of using what I use at work, at home, so I can get more “in my bones” experience with those technologies. (Still haven’t figured out a good in-home use for LVS, Varnish, or Memcached, but I’m sure they’re out there.)

That’s where the title came from: we use ‘Thumpers’ a lot at work (actually, Thors now, but the same idea.) Sun’s X4540 and X4500 are 48 SATA Disks in 4 Rack units and they run Solaris and use ZFS to do the magic. This is going to be a teensy little version of the same idea.

So, what’s the solution. MSI is a well-known maker of ’netbooks’, those tiny, battery sipping, low priced laptops. It turns out they made a desktop based on the same Intel Processor, the Atom. It’s the “MSI Wind PC Barebones” and it has a lot of appealing attributes.

1. Price: It's $155 (but you need to add RAM and disks.)
2. Power usage: I haven't hooked up a Kill-a-watt yet but this should be quite efficient.
3. CF Card slot on board: you can install an 8GB card on board, use that for your OS, and use the drive slots for nice clean data. This helps with power usage, since we can spin down our data drives more often than system drives.
4. USB ports: it's got a ton, and since I plan to expand via USB drives, this is nice.
5. 2x internal SATA bays: I can install 2 drives onboard to start with.
6. OpenSolaris, my operating system of choice for this application, is 100% supported. (Well, at least the parts I care about. I did not test the sound driver.)

Here’s the parts and prices:

Total Price: $456.98. (No tax or shipping from Amazon, since I am a Prime Kind Of Guy.) Compare that to a Drobo for $424.49. For an extra $32 I have a full, 3TB raw storage system instead of just an empty enclosure to start sticking drives into. And the benefits of having a server online, as well – a drobo’s not that fun unless you plug it into something.

So how do I expand if I need to? Simple! Start adding in USB drives as needed! There is a great guide to doing just this on one of the Sun blogs, which includes some nice pointers about how to set this up.

The install was CAKE, the hardest part was finding a monitor and keyboard as I am only laptopped at home. Well, the hardest part was making an install USB device, but you already known how to do that.

Also, to install the CF card into the Wind, I had to remove the motherboard – that’s the only way you can slide it in. Minor annoyance but worth noting.

After that it was a simple matter of setting up the zpool with my new drives, and exporting the filesystem to my other devices.

    # Use the format tool to find the disk ID's in the system
    jbarratt@rothko:/$ pfexec format
    Searching for disks...done
    AVAILABLE DISK SELECTIONS:
        0. c5d0 <default cyl 3820 alt 2 hd 128 sec 32>
            /pci@0,0/pci-ide@1f,1/ide@0/cmdk@0,0
        1. c6d0 <st315003 -         9VS0MPD-0001-1.36TB>
            /pci@0,0/pci-ide@1f,2/ide@0/cmdk@0,0
        2. c7d0 </st315003><st315003 -         9VS0BXT-0001-1.36TB>
            /pci@0,0/pci-ide@1f,2/ide@1/cmdk@0,0
    Specify disk (enter its number): ^C

    # Create the pool as a mirror between my 2 1.5TB drives
    # zpool create apool mirror c6d0 c7d0

    # Create a filesystem
    # zfs create apool/archive

    # Share that over NFS
    # zfs set sharenfs=rw apool/archive
    </st315003></default>

And now the contents are flying over my network and filling it up. I’m excited to do a few more things soonish:

• Get the FMA (Fault Management) set up so I get emailed/SMS'd when alerts about hardware glitches happen
• Get mdnsd correctly broadcasting the host's name on the LAN so I can use that for services
• Migrate my existing data onto the server and add the now liberated USB disks to the pool
• Set up automatic scrubs and snapshots
• Designate a 'critical' area of the disk and rsync that subset of the data out into a 'cloud storage' service
• Figure out what my power usage is under load and when the disks are spun down
• Put the system on a UPS

On the other hand, it already works pretty great and I can probably survive with it as is for quite some time. Now, to free up some of my precious laptop hard drive space without worrying about a drive crashing.