Axiom Home Page Forums General Discussion The Water Cooler Mac guys and gals: ? about external HDDs

Hallo folks,

I know our resident Mac experts have to have experience with external HDDs. A friend of mine wants me to throw a couple together for him. In researching the subject, I've found that Macs can occasionally turn E-HDDS into paperweights, or at least destroy data. This tends to happen either when the OS is upgraded or when the drive is not disconnected in the correct order.

My question is: Are these just stupid user tricks or are there gotchas you can illuminate for me? Also, I am assuming that an external drive built from off-the shelf components that incorporate industry standard tech (SATA, SATA II, Firewire 400/800, etc) should pose no problem. Am I safe in that assumption? Most Mac users I have come across don't have the DIY gene as far as confusers go, so I'm hoping y'all can expand my horizons.

LJ

I always blame the users. Basically, just disconnect the drive (by ejecting it in some way shape or form) before running Software Update.

Your second paragraph is just fine, except the bit about the DIY gene--some people just go nuts. See url=http://www.xlr8yourmac.com for the crazies.

eSATA will be a problem, of course, unless you have a card for it.

There's also some issue with NCQ and the newer machines, so just avoid those drives--but if you're talking externals, you're fine.

As far as the DIY gene goes...I've built every computer I've owned as well as my family's and close friends for over10 years now. That's what I mean by DIY. As far as Native Command Queing I believe A) Most if not all newer SATA drives have it in their logic and B) A bit needs to be flipped at the OS level for it to be active. I wouldn't be suprised if "Leopard" implements this performance enhancement.

Thanks for the input. The ability to choose the best available components at commodity price is the essence of the DIY geek. Glad to hear the Mac is amenable to DIY periphs.

BTW I recently leveraged my new CS degree into a new job as Director of Information Services at a credit union here in the PDX area. Good things do indeed come to those who toil. Had to give up my G4 Powerbook but am going to start acquiring MacBook Pros here as soon as the Merom chips are available on that platform. Bootcamp here I come! By then I suspect the teething problems vis-a-vis batteries, fans, and noise will be worked out. As a Uni/Linu/x stalwart I am frothing at the mouth. Our CU employs an HP-UX host at it's core and I couldn't be happier. Actually we are replacing it within a couple of years and I'm pushing for an IBM z-Series . Caloo, callay! What a frabjous day! GEEkgeekgeekgeek!!! I think I just had an orgasm.

LJ

The most important thing to do is figure out what chipset is in the external bay you are planning on buying. Odds are you'll want to go with 1394 for the Mac as the external bus. Inside the drive bay it might be IDE or SATA, the OS doesn't actually know what kind of drive is in the bay-it will treat the drive as a 1394 drive. It is up to the electronics that translate from 1394 to IDE/SATA/SCSI to enable fancy bits. If the enclosure is for IDE drives and you are planning on putting a 130gig or larger drive in the bay make sure that it supports a feature called '48bit LBA' which roughly translates to 'drives bigger than 127 gigs'. If it doesn't support this feature then it will treat large drives as 127 gigs and you'll probably want to throw it at the wall. For SATA you can assume that big drives will work.

I am going to stress this as I tested 1394 devices, including hard drives, in a previous life-research the 1394 chipset that is in the bay you are planning on buying. There was one that was known for being really fast-if I heard it I'd know it. There are a few out there-and its been awhile so I don't remember which ones but Agere comes to mind-that had some fun bugs like 'oops your data got deleted because you plugged a camera in while you were using the hard drive'. Personally I'd avoid the DIY route for this and just grab a well known brand off the shelf.

You're looking for the Oxford 911 or 912 chipsets, I think.

Thanks for the responses. Once we finally get rid of ATAPI/IDE all will be well in the world.

So I went to the local computer store and picked up an "I-Rocks" combo USB 1.1/2.0 and 1394/1394a enclosure and a 250GB Seagate IDE drive, threw them together, and the Mac picked it up instantly. Just had to initialize and format the drive. No fuss no muss. Cool how you can put an OS 9 "driver" on the drive for backwards compatability. I would guess the driver is an abstraction layer between OS 9 and the OS X filesystem. Cool beans anyhow.

Funny how I got so worked up about doing this for a Mac. I've got external drives running on my Windows and 'ix machines that I threw together and never had a problem. Just was a little jittery about the "my drive puked and lost all my data" thing. My friend though does have a couple of external Lacie drives and says he always un-mounts them correctly and has never had a problem so I think this one will work fine for him.

LJ

Actually, the OS 9 compatibility just lets you install OS 9 on the drive itself. An OS 9 machine can still read a drive without that format tag, just can't boot from it.

Yeah, usually externals are just fine on the Mac. I don't use 'em personally (for no good reason, other than I don't like peripherals in general).

Gotcha, that's what that is for. I should have paid closer attention. Not that it matters much anymore, my friend's machines are all OSX now except 1 and that one can boot to either.

He owns a little recording studio and backs up projects to external drives as well as DVD. At least the projects that are done in Pro Tools. He has an Otari 2" 24 track recorder as well. Through a pretty complicated patch setup he can record through his old 70's era mixing board with nice built-in preamps on every channel to either the Pro Tools system or to the tape machine.

Funny how 10 years or so ago you couldn't touch even a used Otari for under like 30K and just last year he picked up the board and the Otari for 5K. I tell you, listening to the stuff he records there is something about the analog board/tape sound that just sounds right depending on the style. Folk, blues, jazz, punk and "grunge" just sound right the old school way. Horn bands, hip hop, the rest sound great on the digital side.