1 Topic by ronbaby

  • ronbaby
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  • Registered: 2012-09-04
  • Posts: 49

Topic: Delete partition table?

Maybe I'm just missing something.

Looking at both the current online documentation for gparted and also at the GUI, I see that it is easily possible to -create- a fresh new partition table on a given device, but for the life of me, I don't see any button or knob that would allow me to either -delete- or -replace- an existing partition table.

Seems rather non-symmetric to me.

Did I just miss something?

This comes up for me from time to time.  Like, for example, I'll have an old drive with a GPT on it, and I want to change it to MBR, or vise versa.

Do I really have to shut dow the whole system, boot some flavor of *nix, and then dd a bunch of blocks full of /dev/null to the device in order to kill off an existing partition table?


P.S.  I don't know much about this stuff, but as I understand it, fully killing off a GPT partitioning table can be somewhat non-straightforward, in that one may have to overwrite the copy of the GPT that is at the start of the drive, and then also, for completness, write zeros also over the backup copy of the GPT that sits at the far end of the drive.  Is that correct?  If so, then fully zapping an existing GPT gets tricky, and this is exactly the kind of thing where I would most hope that gparted would ride to the rescue and help me to get the job done properly.

In short, I guess that I am stating a new feature request.  Please implement partition table deletion.  And please handle the annoying/tedious parts in the case of GPT deletion.  Thanks.

2 Reply by class413

  • class413
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  • Registered: 2007-05-25
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Re: Delete partition table?

Hello.

Normally, creating a new partition table (or "disk label" according the legacy IT terms) overwrites the existing partition table and installs a new one.
In a few cases it seems that some software is confused by the eventual remaining sectors of the previous disk content.
Please note that we have no detailed reports to know if this comes from older partition tables or partition boot sectors or any previously stored info on the HD space.

Example: the MBR it self is just one sector, the sector #0. The remaining sectors up to #63 are left unused, but they are often used by software programs as bootloader space or unofficial MBR backup copies or to store commercial software authenticity info (at least in the past) etc. Creating a new partition table would overwrite the first sector but would leave intact the remaining space that isn't normally used by any software. GParted tries to make the minimum required changes on the drive space, giving chances of recovery in case one needs it.

Of course, a non standard acting software can be confused by these remains. In this case, we can solve the problem by overwriting with zero the first few MiB of the drive, as well as the last ones in the case of GPT. This can be by the dd command from the terminal window (as root). GParted contains the dd command, so you don't need any additional O.S. for this.

I can't reply now for problems in case of other types of partition table or configurations like LVM, RAID.
You can post the request in the special request section of the Forum.

*** It is highly recommended to backup any important files before doing resize/move operations. ***