Re: Disk Utility and Disk Repair

Jolly Roger wrote:
On 2007-07-02 16:40:23 -0500, The Natural Philosopher <a@xxx> said:

Jolly Roger wrote:
On 2007-07-02 15:58:12 -0500, Steve Ball <steveb@xxxxxxxxxxxxxx> said:

Jolly Roger:

On 2007-07-02 10:14:45 -0500, John Byrns <byrnsj@xxxxxxxxxxxxx> said:

In article <roWdndi4l74hjBTbnZ2dnUVZ_jSdnZ2d@xxxxxxxxxxxx>,
Tim Lance <see.sig@xxxxxxxxxx> wrote:

On Mon, 2 Jul 2007 09:46:17 -0500, Cris wrote
(in article <Zc8ii.3$4J.2@xxxxxxxxxxxx>):

With 10.4.9, I thought I could repair the disk right from Disk Utility
instead of using the installation CD. Now the repair button is grayed
out and I can only verify it. Has it always been so and I'm just senile?

Most grateful.

You may still be senile, but no, you can't repair a boot volume.

You can test it but must be booted from install media (or other, such as
DiskWarrior, TechTool, etc.), external bootable drive (such as a backup -
you
*do* have a backup?), or another Mac.

How do you boot from "another Mac"?

I think he means that you would use Firewire Target Disk mode.

If you connect two Macs together with a Firewire cable, shut them both
down, then hold down T at startup on one of them to boot into Firewire
Target Disk mode, you can boot the other Mac and Mac OS X will mount
the other Mac's startup drive on the desktop.

More info: <http://docs.info.apple.com/article.html?artnum=58583>

Yes, but can you boot from that disk?

You can't repair the startup disk. So why would you *want* to boot from it when the whole point of the exercise is to be able to repair it?

You boot from a system that doesn't need repairing, in order to have an operating system that CAN repair the disks that you are NOT using to boot.

Huh?

That's exactly what I just said, is it not? Please read the entire thread before commenting - you are saying the exact same thing I just said as if you are somehow adding to the conversation.

Like I said, you can boot the problem Mac in Firewire target disk mode, then connect it to a good Mac to repair the disk that is mounted with Firewire target disk mode.


Changing disks under the feet of a live system is almost guaranteed to get you into deeper water than you are already.

I have no idea where you got the idea that anyone was talking about swapping disks while the operating system is "live" or running.

Its very simple. Stuff the installation DVD into the computer DVD slot, boot it, and instead of using any of the graphics options, select 'terminal' from the menu at the top.

You now have a computer running off a read only DVD ROM, a RAMdisk, with the actual hard drives mounted in /Volumes/something..can't remember. And a root permissions terminal session that can run Fsck on whatever you like. Except the DVD of course :-)

Why are you making this so complicated?

There's no need to go into a terminal window. If you have the installation CD/DVD, all you need to do is boot from the installation CD/DVD, then run Disk Utility from the menu bar, and repair the problem disk.

If you don't have the installation CD/DVD, and you have another Mac that is functioning well, then you can do what I said above - connect a Firewire cable between the two computers, boot the problem computer in Firewire target disk mode, run Disk Utility on the functioning computer, and repair the disk mounted over the Firewire connection.

Easier still, IMHO, to boot from the bootable back-up and run Disk Utility on the "normal" startup volume...well, except that I tried this, and got a message that said something to the effect that the volume I wanted to repair couldn't be unmounted. Another stumper for me.

- E
.