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Change MBR to GPT on external hard drive with data:

I found a way for the internal one here. However the External drive is a Data drive only, I dont't need to care about any bootloaders etc. So is there an easy way to do it? It is a 3TB external drive, the setup in Gpartet looks like that:

| 8MB unallocated space|1,36TB ntfs with ca 300GB of data|1,36 of unallocated space|

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up vote 2 down vote accepted

Note: Like all operations involving partition manipulation, the below procedure carries some risk, and you are strongly advised to backup any critical data beforehand.

If this is a data drive only, I believe the start/end margins are sufficient, and a simple sudo gdisk /dev/sdX (follow steps) should do the job, converting the MBR to a GPT.

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when I type it in it gives me Partition table scan: MBR: MBR only BSD: not present APM: not present GPT: not present *************************************************************** Found invalid GPT and valid MBR; converting MBR to GPT format. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by typing 'q' if you don't want to convert your MBR partitions to GPT format! *************************************************************** Command (? for help): do I have to pu a "w" here? – miceterminator Jul 26 '12 at 20:14
Please verify the partition layout stays the same with p, and then write it with w -- that should do it... – izx Jul 26 '12 at 20:17
worked like a charm thank you – miceterminator Jul 26 '12 at 20:21

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