Project Crossbow is an innovate, and I think important, new contribution to the OpenSolaris project. Crossbow makes network virtualization and resource management first-class citizens in OpenSolaris. If follows in the footsteps of ZFS by having a simple and easy-to-understand interface, while providing great flexibility and power to the administrator. Crossbow can only be found in OpenSolaris, and is not available in Solaris 10. My February column for ;login: Magazine describes and explores Project Crossbow in detail. You can download it here, but as always I encourage you to become a member of Usenix, thereby gaining access to all of the content of ;login: (along with many other great benefits).
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Recovering from a deleted Mac OS X RAID group
Well, it’s been a while since I blogged here. Mostly I’m posting at twitter, and “officially” blogging at my company’s site – ctistrategy.com.
Still though there are things that don’t fit in twitter and aren’t appropriate for my company site, and I should talk about them here… and I will.
This time I want to describe a nightmare I had (unfortunately not while sleeping) and the solution.
On my Mac Pro, I accidentally deleted an important RAID set. I actually have multiple RAID sets. I have a “production” one and a “backup” one, as well as an off-site one in case of disaster. I just do RAID-0 (striping) for performance, figuring with the multiple copies I can recovery (almost) all of the files I need. I keep the production and backup disks synchronized via a great program called “superflexiblesynchonizer”. I’ve tried many and this one actually works.
Further, the important day-to-day stuff I work on is stored in a separate, encrypted, disk image. This Mac feature is very nice. Using “disk utility”, you can create an encrypted disk image. Mount that image up and give a password to use (and create) files there. Then unmount it when done returning the files to their encrypted container. I synchronize that file’s contents to my MacBook Pro. So essentially I have 4 copies of my most important content, and three copies of the other content (photos, music, movies, etc). That certainly seems like a nice safe way to store my files… Except that the off-site copy is frequently multiple months out of date. And when I need to expand the storage in my Mac Pro, I usually have to delete a RAID set, rebuild it on bigger disks, and recopy the data – leaving me a bit vulnerable (or at least leaving my data vulnerable 
during those procedures.
Well, I did such a rebuild, but during the procedure somehow deleted my backup RAID group and my primary one. Fortunately I had my off-site still but I had lots of photos, songs, etc, not stored in that off-site. There is no official way to recover a deleted RAID set on the Mac. I called Apple support and they essentially said “you are out of luck”. I did more research and found some expensive services that would accept shipment of the disks in question, muck with them for an indeterminate amount of time, and return them, either fixed or broken (expensive charge incurred regardless).
Finally I found a forum where someone mentioned that a company called SoftRAID might be able to solve the problem. SoftRAID makes RAID software (essentially a better version of software RAID to replace using the RAID built into the Mac and usable via “disk utility”). But in doing that their software also can convert Apple software RAID to their RAID structures, so they know how Apple RAID works. Low and behold, after a few exchanges of email and configuration files, they sent me some blocks to write over my deleted RAID disks, recreating the RAID structures there. I happily paid them their modest fee (which included a license for their software) and now I’m very happily running their RAID software with my recovered RAID sets. Phew! Very glad I found them and they did a great job getting my RAID set back. Now not to delete anything ever again!
New column posted – Appropriate uses for Sun’s T-Servers
Sun T-servers (also known as “CMT” or “coolthreads” servers) are low-cost and high capacity. But they are not a perfect fit for all workloads. My latest column goes through the details and how to determine if the T-servers are a good choice for a given application workload. It’s available here.
Nice list of software that works / doesn’t work on Snow Leopard
I’ve started updating my systems, but first checked the compatibility list published at http://snowleopard.wikidot.com/ to be sure there are no known problems with applications that I care about.
I’m starting from least import and moving toward my most important systems. For my main desktop I’ve ordered a new hard disk to install as the boot drive. I’ll first install it externally, have the Snow Leopard install disk copy my current boot disk contents there, and then perform the upgrade there. Provides a nice safety net in case there are problems with Snow Leopard…
Bigger and faster
Just upgraded my macbook pro with a newly-available 500GB 2.5″ SATA 7200 RPM drive. It was simple and quick and now I have more, fast space on my internal hard drive.
Here are the steps:
- Purchase the drive – I got mine from macsales.com otherwise known as Other World Computing.
- Attach the new drive as an external drive in an external chassis. Fortunately I already had one, but OWC also sells those. Something like this would do the trick. (Note that Firewire is faster than USB but that both would work.)
- Use Disk Utility (it comes with Mac OS) to format the new drive. I chose partition-> 1 partition, Mac OS X Extended (Journaled), then pushed the “options” button and chose “GUID Partition Table” as this is an Intel-based Macbook.
- Use Disk Utility to copy the internal drive to the new external drive via the “Restore” option along the top of the main window. This step took ~2 hours using FW400, copying about 200GB of content from the old disk to the new.
- Halt the system, remove the old hard drive and replace it with the new drive. Fortunately on the new MacBook Pros, this is easy. The old systems were challenging to get into and to change disks in. Although again OWC has the directions.
- Boot the new system and revel in its speed and free space!
Upgrade memory – get out of jail
Upgraded the memory on my Mac Pro from 5GB to 12GB and I feel like I’ve been let out of jail. Now I can have Entourage, Firefox, Aperture, and Vmware running at the same time and not be swapping to disk – life is much faster. I used 2 X 4GB kits from Other World Computing – a great company. Removed the 2 X 512MB DIMMs that were the original memory in the box.
Sun 7000 FAQ published at CTIStrategy
The Sun 7000 is a new NAS storage line from Sun. It contains lots of new ideas, and some of those new ideas can be a bit confusing. My colleague Jesse St. Laurent has taken the lead on clearing up the confusion by writing the Sun 7000 FAQ. Have a look at it and feel free to add questions (or answers) via the form at the bottom of the page.
Teaching at the Usenix ATC conference
I’ll be teaching two days of my Solaris tutorials at the Usenix ATC conference in San Diego during the week of June 15th. Hope to see you there!
Column – The Sun Virtualization Guide
My April 2009 column has been published in ;login: Magazine. This month it’s The Sun Virtualization Guide- making sense of and decisions about the various Sun virtualization options. LDOMs, Containers, Domains and Xen are all options worth considering, and this guide leads you through what each does and when to use them. Some ;login: contents is freely available at ;login:, but my column this month is not one of them. I’ve posted the .pdf here for those without a USENIX membership (although I strongly recommend you get one if you are interested in all things Unix).
Usenix 2009 Registration open
Registration for the 2009 Usenix ATC conference has just opened. The conference is top notch, for and buy Unix administrators. It’s in San Diego, CA the week of June 15th. I’ll be teaching two tutorials there (covering Solaris 10 administration, virtualization, file systems, and security) and hopefully will be around for the whole conference. One of the keynote speakers is David Brin, and I’d love to meet him.
Full information, schedule, and information is here. Hope to see you there.