njr 3.0

As a followup to my prior post on external enclosures, a helpful commenter mentioned the OS X SAT SMART Driver, a third-party driver which provides SMART monitoring via USB/FireWire on OS X.  Other operating systems provide SCSI command pass-through support, meaning a separate driver is not required.

The installation instructions for the driver are confusing and contradictory in places, but you should be fine if you download a snapshot of the repository, install version 0.6 from the included disk image (SATSMARTDriver-0.6.dmg) and restart, then look in Disk Utility to see if SMART status appears for your drive (which may take a minute or two).  I had no problems on 10.6.8 or 10.8.4.

However, works just means the SMART driver is functional — the USB or FireWire enclosure/SATA bridge you’re using needs to support sending SMART commands to the drive as well. As is customary with “fringe” features of commodity hardware, reliable information about specific hardware support is hard to come by. The best I found was this list of USB devices supported by the smartmontools package (which also includes some notes on FireWire), but it doesn’t include most of the devices I have.

I originally used a Linux live CD with smartmontools preinstalled to test several of my USB 2/3/FireWire 800 enclosures. This provides more useful error information than OS X when SMART doesn’t work, but the set of devices supported by the OS X driver turned out to be identical.  (This is not necessarily the case.)

The results weren’t great — links point to smartmontools output:

• Seagate GoFlex Pro for Mac — fine via USB 2, no good via FireWire 800 (separate bridge).
• Hitachi Touro Mobile USB 3 — fine via USB 2 or 3.
• ICY DOCK MB559UEB-1S with 1.5 TB Seagate ST315003, Oxford OXUF924DSB — no good via FireWire 800 or USB 2.
• Newer miniStack v3 with 2 TB Samsung HD204UI, probably the same Oxford bridge — no good via FireWire 800 or USB 2.
• Plugable USB3-SATA-UASP1 with 1.5 TB Seagate ST315003 — fine via USB 2 or USB 3.
• ICY DOCK MB080USEB-1SB with 750 GB Seagate ST3750330 — fine via FireWire 800.
• Old, cheap USB 2 enclosure with 80 GB Seagate ST980821 (ATA) — obviously not going to work, but included for completeness.

Assuming the above is representative, if you're using a USB 2 or 3-only enclosure, chances are good that you'll be able to get SMART info. If you’re using an older FireWire 800 enclosure, you’re probably out of luck, even over USB. If you’re using a newish FireWire 800 enclosure, it might work!

The MB080USEB-1SB above is a nice toolless swappable FireWire 800/USB 2.0/eSATA enclosure with a large (quiet) fan up front. It is available until the end of August for as little as $38 after a $40 mail-in rebate, which is a pretty great deal if you still need FireWire 800, and it was the only enclosure I tested that does support SMART over FireWire.

Speaking of fans, OWC now sells replacement fans for the miniStack — mine seems to have fixed itself as I discussed in my prior post, but it’s good to see the option.

12:52 PM | Computing