Reformat / resize an external hard drive removed from a NAS I have a 3TB hard drive that I removed from a NAS that is only showing as 800MB on my Mac.

Have tried Disk Utility (and terminal diskutil) but the hard drive keeps showing at the wrong size.

diskutil:



Disk Utility (Debug -> Show every partition):



Partition tab:



The disk in question is the one showing as 801.6 / 801.57 GB. It is in fact a 3TB HDD.

I appreciate that this is something to do with Linux and the mac not reading ext2,ext3 etc..

Don't mind losing all the data on the HDD, just cant figure out how to reformat this drive.

Thanks in advance for any help.

EDIT

I believe this could be an issue with the caddy that I am using not supporting HD greater than 2TB.

Will source an alternative caddy to confirm this.

EDIT

This problem was due to the caddy not recognising HDD greater than 2TB. Is a common problem on older hardware.
Quit Disk Utility. Try this command in the terminal:

defaults write com.apple.DiskUtility DUDebugMenuEnabled 1


Relaunch Disk Utility. Select Show every partion from the now present Debug menu. See if you can find some hidden partitions and remove them!