Clearing a GUID Partition Table (GPT) in Linux PDF Print E-mail
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This is more of a note for future reference rather than a blog post.

I recently had to replace a RAID-10 member disk as the original disk had developed bad sectors and was causing mostly read related problems in the array. (That’s a whole other story it it’s won right and I don’t have time to get into that now). However, when I tried adding the replacement disk to the server, I found that the disk had a GPT table and not an msdos partition table, unlike the other 3 members in the RAID array. I was therefore unable to add the disk “as-is” to the RAID array as all disks are required to have the same partition table type. I therefore needed to remove the GUID Partition Table and replace it with an msdos partition table.

My initial though was to use fdisk. However, fdisk does not understand GUID Partition Tables and therefore cannot remove such tables. The other tool that does understand GPT is a tool called “parted”.

So to replace the GPT table with msdos, I did:

parted /dev/sdc
mklabel msdos
quit


If you are running Windows and would like to clear a GPT table, you may use the "clean" command in diskpart (Diskpart can be accessed from the command prompt)