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How To Convert a GPT Disk Back to an MS DOS type MBR Label

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Here's a real quick HowTo showing how to manage that pesky conversion when you want to convert a GPT disk to an MS DOS label.

I wrote this up real quick for my good friend arrozcaldo, and thought that I would just go ahead and share it with everyone else too cool

I'll leave this on the front page for a few days, and then move it to the blogs section, where you can find lots of other little tidbits of quick info for common tasks that I keep on hand for easy access in the form of an online cheatsheet...

Removing GPT information from a drive



Method #1:

1. Press CTRL-ALT-F2 or F3.

2. Type "parted /dev/<devicename>", usually "parted /dev/sda".

3. Once inside parted type "mktable":

  -> Table type: msdos

  -> Destroy data: yes

  -> quit

4. GPT should now be removed.

5. Continue with install.

Method #2:

1. fdisk -s /dev/<devicename> --- This gets the blocksize of the device.

  Make the last five digits of this number zeros. Example: fdisk -s /dev/sda

  Will show an error about GPT, and then the block size: 39078144

  Change to 39000000 which equals our blockcount

2. dd if=/dev/zero of=/dev/devicename bs=1k seek=blockcount

3. dd if=/dev/zero of=/dev/devicename bs=1k count=20

Method #3:

1. Press CTRL-ALT-F2 or F3.

2. Type: "dd if=/dev/<devicename" of=/dev/zero bs=4k"

3. When done, continue with install.


I like method one - it's flawless and easy, but you have to have parted installed.

I hope that helps :)