How do I boot up from an external hard drive?

[murrs]

I want to make a bootable clone of my iMac (PowerPC G5 running OS 10.5.8) and also backup my MacBook Pro onto an external USB hard drive so that I can restore from the external hard drive if my iMac dies (which is beginning to have startup problems).

I was planning to create 3 partitions - one for iMac's data which I'll continue to backup using TimeMachine, one for my MacBook Pro's data and one partition as a bootable clone of my iMac.

My question is.... if my iMac dies, how do I use the external hard drive to boot up from? Do I need Carbon Copy Cloner or will I be able to boot up from the external hard drive and access Apple's Disk Utility?

 

[spinnerlys]

To boot from an external HDD, just hold down the OPTION/ALT key right after the startup sound chimes and select the OS to boot from.

With PPC Macs you need a Firewire connection, Intel Macs can also boot from USB connected HDDs.

To have a bootable copy, you need a clone via CarbonCopyCloner or SuperDuper. Time Machine is not bootable.

Once booted from an external HDD, you can use Disk Utility like you want.

 

[SDub90]

I believe you need a firewire drive to boot up a PowerPC mac off of an external device.

You can use carbon copy cloner to make a bootable backup to the external drive then use your macbook pro to duplicate that to a new internal drive if your iMac ever ***** the bed and you replace the drive.

edit: spinnerlys replied while I was typing.

 

[GGJstudios]

Easily boot from USB 2.0 drives on PowerPC Macs

 

[spinnerlys]

Easily boot from USB 2.0 drives on PowerPC Macs

Thanks for that information, I only knew of three models who could boot via USB.

I will try it with my iBook sometime.

 

[murrs]

Easily boot from USB 2.0 drives on PowerPC Macs

Thanks for the link! I just realized that I can't boot my PowerPC from a USB external drive after I made my post. I can't return the drive either so I hope the tips in that article will work.

I probably wasn't that clear in my earlier post ...What happens if I can't use the Option key when starting up my iMac?

Last week my iMac wouldn't start up at all (I got a blank gray screen). Holding down the option key didn't work either. I managed to fix it by starting up in single user mode and using fsck at the command line to repair the disk.

My fear is that it's likely to happen again as it still takes 3 attempts before my iMac successfully starts up.

Thanks for all your help so far!

 

[DewGuy1999]

Thanks for the link! I just realized that I can't boot my PowerPC from a USB external drive after I made my post. I can't return the drive either so I hope the tips in that article will work.

I probably wasn't that clear in my earlier post ...What happens if I can't use the Option key when starting up my iMac?

Last week my iMac wouldn't start up at all (I got a blank gray screen). Holding down the option key didn't work either. I managed to fix it by starting up in single user mode and using fsck at the command line to repair the disk.

My fear is that it's likely to happen again as it still takes 3 attempts before my iMac successfully starts up.

Thanks for all your help so far!

If the iMac isn't booting because of a failed internal hard drive and you have the external hard drive attached, turned on and it's confirmed bootable the iMac should automatically boot from it.

 

[Fishrrman]

"My question is.... if my iMac dies, how do I use the external hard drive to boot up from? Do I need Carbon Copy Cloner or will I be able to boot up from the external hard drive and access Apple's Disk Utility?"

Just to make something clear, you CAN'T BOOT from a Time Machine backup, so they are viturally useless in a "moment of dire need" when you have no choice other than to boot from an external volume and get going again. Yes, you _could_ boot from the System DVD and do a "restore", but why go through all that when you can just boot from a "clone" of your internal drive that already exists?

Having said that, once you've created a "clone" using CarbonCopyCloner or SuperDuper, booting from your external drive is a snap.

Just plug the external in (USB2 or Firewire), power it up, then turn on the Mac (even if the internal hard drive is munged and unreadable). The Mac will first check the internal -- BUT -- if it can't find the internal to boot from, it will start "checking around" for another bootable volume. It should find your external with a valid System and boot from that, instead.

IMPORTANT:
Don't wait for a disaster to see if your external drive is bootable. Do some "test boots" from it, just to be sure.

Easy way to do that:
1. Connect the external, let it mount on the desktop
2. RESTART
3. As soon as you hear the startup chime, hold down the "option" key and KEEP HOLDING IT DOWN
4. The "Startup Manager" will appear.
6. Use the right/left arrow keys to select the volume from which you wish to boot, then hit the enter/return key.
7. The Mac will boot from the selected volume.
NOTE: This WILL NOT change your "startup disk" preferences. The NEXT TIME you boot, it will boot from the internal again