A SoftRaid setup in OSX Lion, using the Sharkoon eSATA enclosure

Another very nice enclosure: the Sharkoon 5-bay eSATA/USB box. It is compact, quiet and stylish, plus: the disks can be swapped without the use of special tools/frames, which makes it very convenient.

It’s attached to my HackPro via a two-port Sonnet Tempo E2P (mini PCIe) card, so some of the information in this post will be specific to this (Silicon Image 3132-based) card. Apparently, even the ExpressCard3/4 variants of the Si3132 chip, which are widely available, work quite well with the latest drivers from Sonnet – last updated on November 29, 2011. Based on my (limited) research, this archaic chip from Silicon Image provides much better functionality – e.g. port multiplication, hot swapping – as well as stability, compared to the newer 6Gb/s offerings from other manufacturers. Granted, there are some glitches (my MacBook Pro kernel occasionaly panics with the ExpressCard on boot up), but data reliability is not jeopardized as with other chipsets. The OSX86 machine runs beautifuly, with many weeks’ work of uptime, albeit with some trouble which I’ve managed to troubleshoot (see below).

So, the setup is as follows: two 5-disk enclosures are directly attached to my Mac, each with an assortment of non-RAID and mirrored arrays, depending on the importance of the data. For example, enclosure A stores my work-related stuff (in a 3-disk mirror), while enclosure B contains audiovisual stuff: a huge Adobe Lightroom catalog in a two-disk mirror, and my home video projects in another array. Most hard disks are WD 2Tb “green” models.

Needless to say, each array is backed up to a Netgear ReadyNAS Pro, as well as a Solaris Express server. Oh, and a time machine backup of my office data also takes place, along with a SuperDuper clone of the root volume. Can’t be too careful (or too paranoid) with data, you see.

Why SoftRAID?

Well, by now it should be obvious that data reliability is the main rationale behind this setup. For this reason, I opted not to use the Sharkoon’s built-in RAID5 scheme, as it would render the array useless if the box went down; I’d rather manage individual disks myself, since this would offer some hope of salvaging data lost to hardware failure (and would not require hiring a recovery bureau).

Apple RAID would be the logical choice, but it leaves a lot to be desired, even under OSX Lion. There is no troubleshooting, no user notification and no GUI to manage the arrays. Disk Utility has messed things up after a disk failure, requiring reinitialization of the array, and I still can’t get over that. It might be me, but one does not get a sense of security with Apple’s RAID implementation.

The only software RAID projects available for the Mac are: SoftRAID, a commercial application, and MacZFS, which is open-source and free. I think that both are great! I’ve opted for SoftRAID for my work data, as it appears to be top-notch in terms of functionality, reliability and support. Granted, it does not offer the sexy features that ZFS-based solutions claim (e.g. protection against “silent data corruption”), but, to my mind, they apply to server-grade, not the direct-attached (DAS) storage units we need for daily desktop work. A three-way mirror usually suffices!

MacZFS, I use for music and (non-pirated) video collection which resides on a Lian-Li eSATA enclosure (5*1Tb). The bonus feature is that the box can be shared by a Solaris server and extend its capacity (albeit under an old version of ZFS).

Problems

Well, the specific SoftRAID/Sil3132 card/eSATA enclosure combination presented above seems to work very reliably under Lion, and this experience is based on extensive use, over many months. There are 10 disks total, of which only 3 are plain HFS volumes. Most are 1Tb or 2Tb economical “green” models. The 3-disk mirrors can be “split”, so I can remove a read-only copy of the array, take it home and hook it up to (you guessed it) another Sharkoon enclosure connected to a MacBook to review, say, my LightRoom library. The folks at SoftRAID allowed me to license that copy, although it’s not entirely clear how many machines can run the driver with the same serial number.

Overall, I think that SoftRAID deserves a 5-star rating and it’s a steal for what it offers, even to home-office users like me, who require larger than average directly-attached storage (practically everyone, that is!).

There was only one issue which had been irking me, however, from the very beginning: after a finite number of sleep-wake cycles (say over a period of two days), one or both the enclosures would fail to wake from sleep. This resulted in major flakiness, usually culminating in a kernel panic.

I had no clue on how to approach this (googling provided no results), but it seemed like hardware-related trouble, so I started troubleshooting the connections, etc. New eSATA cables, reseated the PCIe card, rotated the disks, changed to a new enclosure, reinstalled the Si3132 drivers (both Sonnet and Silicon Image) – all to no avail. I even flashed the Western Digital drives’ firmware so as to disable the “Intellipark” feature, which too seemed a logical possibility.

Another obvious culprit was my specific OSX86 setup, but I won’t go into details, except to say that I tried all sorts of “darkwake”, “PCIRoot”, “arch” kernel flags, again with no effect. I was too lazy to hook a box to my MacBook Pro (via an ExpressCard eSATA), as that would entail significant delays, while my older Macs are all PPC and could not duplicate the Lion setup.

Troubleshooting was laborious, since the problem manifested itself only after a couple of days’ work of sleep, and trying all permutations took weeks at a time.

Anyway, to make a long story short (and, perhaps, help a fellow sufferer) here’s what cured the problem: Placing a non-SoftRAID disk on bay #1 (the top one) of the enclosures eliminated the disconnection after sleep. As I’m writing this, my Mac has an uptime of 20 days, with a myriad sleep-wake cycles, many intentional disk removals and hot swaps, all without a single hitch.

Things are looking good.

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4 Comments (+add yours?)

  1. Trackback: Article: Review: HighPoint RocketRAID 640L - Page 2
  2. Carsten (the Netherlands)
    Nov 18, 2012 @ 09:39:59

    Thnx for the info! Had same strange problems with my Sharkoon with 4 striped disks. After reading your article I placed a fifth (non-raid) disk in the top and it works flawless now.

    Reply

  3. boscowitch
    May 16, 2014 @ 13:12:09

    Thx for that info, I’m using Linux but had simillar problems. Sine I already put some data on my 5hdd raid I will try to switch off spindown with APM for the top HDD. btw. SMART also diesnt work for the top disk… guess ich gonna dump that case in the future for an internal solution since write speeds are also kinda slow with that chipset no matter how i tuned it.

    Reply

  4. boscowitch
    May 16, 2014 @ 22:45:39

    Switching off spindown seemd to have worked but i think i found an even better solution. I googled for th JMicro chip sharkoon uses in this external case (the JMS539 Sata/USB 3.0 Controller ) and seems like there is a newer Firmware around for it, so far so good I even reactivated spindown for the most top HDD, unfortunatly the firmware does not fix the issues with the missing SMART support for the top HDD. The Firmware and Windows installer can be downloaded from this French Website: http://www.station-drivers.com/index.php/downloads/Drivers/Jmicron/JMS539-Sata-USB-3.0-Controller/JMS-539-Firmware-Version-255.31.3.41.22/
    You only have to find the “Download” Link its in French 😉 (IMPORTANT! After some googling I found the info that the firmware update maybe only works when the case is plugged into a USB2 port updating the firmware with a USB3 plug should not work, but of course you can switch it back to usb3 after the update!)

    Reply

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