[Seamus]

Mounting a bootable .dmg file will make it non-bootable. Does anyone know why the system needs to make a permanent change to the .dmg file to mount it? Shouldn't mounting a .dmg be a read-only operation?

[macintologist]

Sorry, can't help you with that leaked Leopard install DVD you downloaded from torrents

J/k. I have no clue.

[Kevin]

And if you downloaded that 6.1g OS X image file, it's not what it says it is.

[voodoo]

Originally Posted by Kevin 

And if you downloaded that 6.1g OS X image file, it's not what it says it is.

Ah the correct one is 6.56GB.

@the OP:

always lock dmgs and toasts (images) before mounting. One learns this the hard way.

V

[.Neo]

I heard this, but never experienced the problem myself.

Sucks you have to redownload Mac OS X Leopard though.

[Kevin]

Originally Posted by voodoo 

Ah the correct one is 6.56GB.
V

Originally Posted by .Neo 

Sucks you have to redownload Mac OS X Leopard though.

[Eriamjh]

Originally Posted by Seamus 

Mounting a bootable .dmg file will make it non-bootable. Does anyone know why the system needs to make a permanent change to the .dmg file to mount it? Shouldn't mounting a .dmg be a read-only operation?

Because once you reboot, the disk image is unmounted! You can't boot to an unmounted disk!

[Kevin]

No, I think he means why is the image no longer able to burn if you mount it.

I distinctly rememb.. er hearing people telling me that certain images came with read-mes saying to burn with disk copy, and NOT to mount it or burn with Toast.

[FireWire]

That's the first time I hear that! That's a really strange behavior!

[Seamus]

I'm certainly not complaining that it happens (I didn't download the 10.5 GM that is making the rounds, and I don't plan to). I'm just curious as to WHY it happens, as it seems to me mounting a disk image should be a read-only operation.

[Art Vandelay]

I remember hearing about it back in the 10.0 days. If the image is read-only, mounting it will not do anything to it. Even if it was read-write, I don't see how mounting it can do any damage to its bootability.

[Seamus]

Originally Posted by Art Vandelay 

I remember hearing about it back in the 10.0 days. If the image is read-only, mounting it will not do anything to it. Even if it was read-write, I don't see how mounting it can do any damage to its bootability.

Except that it most certainly does damage its bootability, even now.

[Art Vandelay]

Says who?

I've mounted OS X images from Apple many times. Never had a problem when I've burned or cloned their images.

[Seamus]

Originally Posted by Art Vandelay 

Says who?

I've mounted OS X images from Apple many times. Never had a problem when I've burned or cloned their images.

Several people who have downloaded the GM and attempted to boot off a burned copy of the disk after mounting it.

[Art Vandelay]

That's a highly reputable bunch...

Anyway, I had some free time this afternoon at work. So, I tested this theory. Apple's image is read only, so no way to corrupt it. I then tried converting it to read write. The mounted volume was still read only. No trouble so far mounting images before burning. I then cloned Apple's image to a partition. I then imaged that partition to a read write image. I then mounted that image and the volume was read write. I added folders and files to it. I then burned that image. It still booted.

So unless the little pirates out there are using some bizarre methodology of creating a bootable image, mounting a DVD image before burning should not make the resulting DVD unbootable.

[beez1717]

What you have to do is mount the DMG on your computer, and then go into the DISK UTILITY and select the option to burn the disk image FROM THERE.

I learned how to do this when I installed Linux. By doing this, you are burning the data so that it will work as a bootable disk rather then just taking your chances on burning the files, which sometimes are in the wroing places on the disk!

[Chuckit]

This doesn't happen under normal circumstances, but it seems to happen surprisingly often with pirated OS X GM builds.

[Art Vandelay]

Must be karma.

[macgyvr64]

It's not just the OS X 10.5 GM build that's floating around -- I've had it happen with earlier Tiger images I've made, as well as my DiskWarrior backups. It's an odd behavior, to say the least. But it does exist!

[jasonsRX7]

I've created images of all our corporate OSs (ESX server, Windows Server, Suse), mounted them several times in OS X, and never had a problem burning and booting from the images later.

[Eriamjh]

Originally Posted by Kevin 

No, I think he means why is the image no longer able to burn if you mount it.

My bad.

[.Neo]

Originally Posted by Chuckit 

This doesn't happen under normal circumstances, but it seems to happen surprisingly often with pirated OS X GM builds.

Right... Must be that new self-destruct feature Apple installed.

[dragon]

Hi

I have the solution for you on making a image file of OSX leopard so you can mount it and also
burn it so it is bootable. I have tested and it works perfectly I even mounted the image first
before burning. Solution obtained from here
http://www.index-site.com/bootcd.html

Panther/Tiger/leopard method
Special thanks to Apple Discussions Board poster Kappy, I've learned of a new process to clone a bootable CD/DVD of your installation CD. He informs me it works with 10.3 through 10.4.4. While this won't give you a CD that allows you to install third party utilities, it at least will mean you'll have a copy of your installation CD in case the old one wears out, and you can't afford an external hard drive.
1. Insert the DVD/CD
2. Open Disk Utility, and select the DVD/CD from the left side list (select the DVD/CD icon on top)
3. from the DU File menu select New | Disk Image from Disk 1
4. Choose to format the disk image as DVD/CD Master, name the disk image and click Save
5. When the .cdr file is finished select it with mouse and press COMMAND-I to open the Get Info and check the box to lock the file
6. Choose the .cdr file from the left side list, click Burn, and insert a new, blank DVD or CD.

[dragon]

Hi

I have the solution for you on making a image file of OSX leopard so you can mount it and also
burn it so it is bootable. I have tested and it works perfectly I even mounted the image first
before burning. Solution obtained from here
http://www.index-site.com/bootcd.html

Panther/Tiger/leopard method
Special thanks to Apple Discussions Board poster Kappy, I've learned of a new process to clone a bootable CD/DVD of your installation CD. He informs me it works with 10.3 through 10.4.4. While this won't give you a CD that allows you to install third party utilities, it at least will mean you'll have a copy of your installation CD in case the old one wears out, and you can't afford an external hard drive.
1. Insert the DVD/CD
2. Open Disk Utility, and select the DVD/CD from the left side list (select the DVD/CD icon on top)
3. from the DU File menu select New | Disk Image from Disk 1
4. Choose to format the disk image as DVD/CD Master, name the disk image and click Save
5. When the .cdr file is finished select it with mouse and press COMMAND-I to open the Get Info and check the box to lock the file
6. you can now mount the image file now if you want to and it will not interfere with burning it as a bootable disk
7. Choose the .cdr file from the left side list, click Burn, and insert a new, blank DVD or CD.
8. You can even change the .cdr extension to .dmg

[macgyvr64]

That procedure does indeed work, and Locking is key to stopping whatever changes would have been made to the file by mounting it. I've never seen the behavior with other OSes -- it seems to be particular to OS X.

[Big Mac]

It probably writes metadata files to the disk image that screw things up.

[Art Vandelay]

There's no need to lock it. The volume is read only so nothing can happen to it when mounted. I even did a test (see above) where it was read-write and it still worked.

The pirate images that people have problems with are probably made with something other than Disk Utility.