| October 20, 2011 3:23 pm

For the past few weeks, I’ve been teaching a course on Windows Server 2008. As part of the course, it’s pretty common that I need to create (and delete) a large number of Windows Server 2008 machines. Because of all the different configurations (and the fact that installing from a CD or DVD takes a lot of time), I’ve found it very helpful to create ISOs for the installation of the operating system.

On Windows 7, this is really easy. There is a nifty plugin called ISO recorder which automates the process of creating an ISO file from disk. To get started with it, you download the applet, install it, and right click on the disk that you wish to capture. Out comes an ISO that you can mount in VMware or VirtualBox.

But as much as I like Windows 7, I don’t actually use it very often. Most of the time, I’m doing things with Linux or Mac OS X. Luckily, it’s pretty easy to create disk images on Mac OS X, as well.

Disk Utility (available under Applications > Utilities) can be used to create disk image files. To do so, open the program, click on the disk that you want to make an image of, then click on the “New Image” button.


Type in a  name for the image and specify where you would like for it to be saved.

Finally, before clicking on the “Save” button, set the the “Image Format” option to “DVD/CD Master.”


Voila! After a few short minutes, you have a copy of the disk that you can burn to CD/DVD (for students), or to keep as a backup.

Unfortunately, though, the format that the Mac uses for the disk image is .CDR. The most common format for CDs and DVDs is .ISO (and sometimes .IMG). ISO and IMG can be directly mounted in a VMware or VirtualBox, CDR cannot be.

Luckily, it’s also pretty easy to convert a CDR image to ISO. You can do this with “hdiutil”, a command line program. Here’s how:

hdiutil makehybrid -iso -joliet -o [filename].iso [filename].cdr

Note: You do have to create a .cdr image before you can use it.


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