How do you boot from an external hard drive?

[Hombre]

I've read a number of ways to do this, but so far nothing works.

I have a power mac dual G5, running tiger 10.4.11 at 2.5 ghz.
I am attempting to boot from a firewire driven WD Mybook, that I erased and installed tiger 10.4.11 on as a mac os extended/journaled volume.

The my book WD drive shows up under system prefs as a bootable drive, but when I choose it, the G5 defaults back to the main internal drive.

Holding down the option key when starting up results in nothing...the G5 won't start at all. Dittos for the command/control/shift/delete idea.

I would like to be able to do this, because I want to take my work and programs from one mac location to another.

Does anyone have any suggestions?

[smartyMAC]

Not sure if starting your mac in "target" mode will boot it from the external drive. But the sure way is get rEFIt. You need not install it on the mac, just burn a CD and then the rEFIt menu will provide you the option to boot from external disk as well. No need of holding down option key.

[harryb2448]

Try holding down option key as rebooting. This should bring up startup selection when external disk connected by firewire, choose external drive and should boot.

[Clairejr]

Check in Disk Utility that the drive is Apple Partition Map and not GUID. If it isn't APM, it won't boot on a PPC Mac. GUID drives will show up in System Preferences as start up disks, but they can only be used to start up an Intel Mac. That may be the problem you're having. I made that mistake the other day with my WD drive (same one that you have, I think) attached to my old PPC Mini and it did exactly what you described. I selected it but the Mini booted into the internal drive.

If that isn't the problem, disconnect any other devices connected to your Mac, especially USB connected devices. The WD My Book Premium has FW-USB conflict problems when it's connected via FW. I had to disconnect all my external equipment until I figured out why I couldn't get the drive to boot with FW. It turned out to be a conflict with an external DVD drive connected via USB.

Claire

[Hombre]

Not sure if starting your mac in "target" mode will boot it from the external drive. But the sure way is get rEFIt. You need not install it on the mac, just burn a CD and then the rEFIt menu will provide you the option to boot from external disk as well. No need of holding down option key.

In 'target mode', it simply doesn't boot up at all.

The rEFIt program appears to be only for Intel Macs: mine is a power PC.....

[Hombre]

Try holding down option key as rebooting. This should bring up startup selection when external disk connected by firewire, choose external drive and should boot.

Doesn't work...reboots back to internal drive.

[Hombre]

Check in Disk Utility that the drive is Apple Partition Map and not GUID. .......

If that isn't the problem, disconnect any other devices connected to your Mac, especially USB connected devices. The WD My Book Premium has FW-USB conflict problems when it's connected via FW.
Claire

It is apple partitioned, and I tried disconnecting everything as you suggested, except the keyboard, and it still booted back to the internal drive after selecting it as the startup disk in system prefs.....

....perhaps I will attempt this on another brand of external HD....or perhaps I will give this up altogether since apparently, my dual processor uses a different form of Tiger than a single processor machine, and going back and forth between the two may not be an option anyway, although the WD drive I am attempting to boot from onto my dual G5 has the same Tiger OS.

[harryb2448]

Hook everything up using firewire prior to booting, then boot and go to System Preferences > Startup Disk and double click. If firewire and the external drive are operable you will be able to select from there and boot from the external disk.

Let's know how you go.

[northy124]

If you are trying to boot from External Drive with an Operating System it won't work last time i checked (not long ago) firewire isn't fast enough for it boot so that might be your problem. If what i have said is not what the thread is about ignore it.

[harryb2448]

Have a look at these comments on bootable Firewire external drives.

http://forums.macosxhints.com/archiv...hp/t-2671.html

Some forums report USB 2 drives will also boot but very slow.

[Hombre]

Hook everything up using firewire prior to booting, then boot and go to System Preferences > Startup Disk and double click. If firewire and the external drive are operable you will be able to select from there and boot from the external disk.

Let's know how you go.

No go friend.

Firewire and the external drive are operable, and I have tried your suggestion numerous times, and it only reboots back to the internal disk. My feeling at this point is that it must have a conflict with the new WD MyBook drive for whatever reason. I have another but older Seagate firewire backup drive that I have only used for file storage that I am going to install 10.4 on and see what happens.

Everyone else, thanks for your suggestions.