Using a mobile hard drive across Mac and Windows

April 08, 2007

I figured I needed some more disk space and it should be mobile, to match my other mobile adventures. So I got myself a LaCie Ruggable drive. First, congratulations to LaCie, smart marketing with the “rugged” stuff. Take an existing hard drive, put a rubber band around it, label it “rugged” and sell it for more money than other people would. But as you see in my case, it worked. And it has survived one flight in checked baggage so it can’t be too bad and indeed feels a bit more sturdy than some of the more delicate mobile gadgets I’ve seen. But is otherwise a very light nice little thing.

LaCie Rugged


But what I wanted to post about was the filesystems. It’s preformatted for OS X, but I needed to use it on both Windows and OS X without any special drivers or other setup. And Windows doesn’t do OS X filesystem. And I didn’t want to mess around with many different partitions, ideally I would have just one partition that both OS-s could read and write to. (OS X can read, but not write NTFS.)

Seemed like FAT32 was the only one matching the formula. Herein comes another great decision from Microsoft – apparently they figured that FAT32 was too slow with larger sizes due to defragmentation, and they arbitrarily capped all Windows disk utilities at formatting 32 GB of FAT32. This means that Windows XP refuses to create FAT32 partitions larger than 32 GB, but once you’ve managed to create it elsewhere, it works just fine.

So a bit ironically, the best solution for me was to reformat the drive in Mac OS X Disk Utility that doesn’t have arbitrary size limits for FAT32. And once done, both OS-es seemed to work fine with it, even though it seemed to be a bit slower than the MacOS filesystem that it originally came with.

One final problem is that I can’t get the volume icon back to its original under OS X. Originally, the drive had a nice custom volume icon in its “.VolumeIcon.icns” file. I made a copy of it, but now when I try to simply copy it back to the FAT32 system, it doesn’t work – the file is copied, but Finder doesn’t pick it up and still shows the default USB/FireWire drive icon :( what am I doing wrong?


Even though both systems support the filesystem, FAT32 doesn’t have any security. And for mixed storage of secure and non-secure data on the drive, I’ll have to resort to user-level applications. I can’t think of a secure multiplatform way, so I’ll probably keep using TrueCrypt for Windows and encrypted dmg images on OS X and when needing to transport secure data, doing it through the intermediate nonsecure area.

UPDATE: one kind of funny thing I forgot to mention before is that the USB cable of the LaCie drive has the same plugs as a Sony PSP cable, with the difference that the LaCie cable is fat and ugly, but the PSP cable is really thin and much nicer, yet still works fine. (When I got rid of my PSP, I somehow still kept the cable.) The only concern might be there that since it’s used by the drive for both power and data, then in longer runs it might overheat, as much more power travels through the thin cable than is the case with PSP? But so far so good.

UPDATE 2: thanks to Paul and Erki, I finally tried out MacFUSE. Which I had wanted to do for a while because of its sshfs support, but never got around to. So I tried, and indeed, it works fine for both sshfs and NTFS. Download MacFUSE and NTFS support from the links given by Erki (need to reboot both after MacFUSE install and the NTFS things install) and then you can read and write NTFS on a Mac. So I reformatted the drive and am now on NTFS without needing to worry about large file support or defragmentation. The only problem here is when I need to use this drive with another Mac for writing (and I’m in a hurry so couldn’t install MacFUSE), but for now, it’s only a theoretical scenario, so I’ll cross that bridge when I come to it.