Use Mac as a fancy external drive

by Volker Weber


A lot of people don't seem to know this. When you hold "T" while a Mac is booting it goes into a firewire target disk mode. Connect this machine now with a firewire cable to a different machine and it shows up there as an external disk. This is the easiest way to exchange a whole bunch of files.


Mac has so many nice features. It is a shame that Lotus is keeping me away from Macs, because there is no Notes Designer available. Same arguement is valid for Linux

Thorsten Ebers, 2004-01-29

Ah, just drop Domino Designer ;-)

Just kidding. I know how you feel... still, there are a couple of rays of hope out there:

1) What could possibly go wrong now that Microsoft own Virtual PC?
2) More seriously, given that 6.51 behaves with WINE, it’s good to hear that Darwine is gaining support.

Ben Poole, 2004-01-29

Anyone tried Firerwire Target Mode with Firewire 800 ports? It must fly!!!

How much does a Firewire 800 cable cost?

idji, 2004-01-30

More boot key combinations can be found at It's even possible to reboot from the external Firewire hard drive. I was able to boot from my iBook's harddrive from my G3 iMac. Of course, this combination then used the iMac's hardware (CPU, graphics, etc.) and the OS X installation on my iBook's hard drive did some reconfiguring of this 'newly found' hardware, but it worked. Kind of useless, I guess, but try to do this with a PC!

The problem with booting the 'external' hard drive using target disk mode is that the target computer cannot be booted into OS X. So it's nice (and very fast) for transferring files from one computer to the other, but I would really like to be able to do that while both computers are booted into OS X. That would be like using a Firewire cable as a kind of ultra-fast peer-to-peer network cable, running at -correct me if I'm wrong- 400mbps or 800mbps. Does anyone know if there's some way to do this?

Pascal Frencken, 2004-01-30

Pascal, you can do that. Go to System Preferences, Network, Network Ports and hit "New". Select "Built-In Firewire". You then have TCP/IP over Firewire. I believe that Windows XP supports the same.

Volker Weber, 2004-01-30

Volker, thanks. I didn't know that, I will try when I get home tonight. I guess it beats transferring files over 11Mbps WLAN, which I now use between de Macs.

Pascal Frencken, 2004-01-30

Taking the train beats walking almost any time. :-)

Volker Weber, 2004-01-30

That's not entirely true, I'm afraid. Try the Dutch railways for a change. I promise you ... walking beats our trains!

Pascal Frencken, 2004-01-30

Well, the train from Mannheim to Stuttgart takes 37 minutes. Walking the same distance (120 km) may be cheaper but takes around 24 hours. :-) The speed difference between Firewire and WLAN is about the same.

Volker Weber, 2004-01-30

Hi Volker,

I have a small but annoying problem on my iMac G3. An Explorer Data with an dmg ending has appeared from nowhere. I think my son tried to load some music and it didn't work. The problem is that I can neither open nor erase this data. When Explorer launches with this data it goes on and on and nothing happens. When I try to erase it a message appears telling me that this data is under use and can't therefore be put in the trash. I know that it's not being used anywhere so I'm totally at loss about what to do to get rid of it. It occupies 7 MB I could use elsewhere. Any ideas?

I'm truly grateful for any suggestion.

Juan Enrique del Solar

Juan Enrique del Solar, 2004-12-14

You may want to try Delete it. You can also do this by hand with opening Terminal and entering:

sudo rm -f filename

Volker Weber, 2004-12-14

Hi, Volker,
I tried the terminal. The answer is: "Permission denied"
The data is on my desktop,but through Terminal I found in which file is located. I got there and I tried to put it in the trash, but again the usual message appeared telling me that the data is used elsewhere.
I must tell you that on the beginning I did something foolish: I changed the name of the data, keeeping though the ending, remembering that on the old MS-DOS this was a way to get rid of unwanted things, but it doesn't work apparently on Mac. (I'm new to this great computer) The added problem is that I can't remember the old name. It's possible that under the old name is really used somewhere. What do you think?
I really thank you for your time and patience. And also for your fast answer.
Truly yours
Juan Enrique del Solar

Juan Enrique del Solar, 2004-12-14

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