[GTALUG] MBR and GTP Drives

[Lennart Sorensen]

On Sat, Oct 07, 2017 at 08:53:37PM -0400, Howard Gibson via talk wrote:
>    I am now completing my most difficult Linux install ever.  My old hard drive with / and /home and /usr/local on it has died.  My new 2TB drive was formatted for GTP.  The Fedora installer warned me that GTP drives requre a /boot/efi partition.  Regardless of how I partitioned, the system would not boot.  I converted the drive to MBR format.  The best I could get was to see the available kernels.  It would not boot.  I got fed up and I bought another new drive, and everything installed and booted effortlessly.  
> 
> Motherboard:  Gigabyte GA-990FXA-UD3 Version~1.1. (Version 3.0 supports GTP)
> New drive:    Western Digital 2000GB SATA WD2003FZEX-0.
> Newer drive:  Seagate ``Desktop HDD'' 2TB SATA. ST2000DM001-1ER1
> 
>    From fdisk, I could see that the Western Digital drive was GTP.  The new Seagate drive identified itself as "dos", which means it is MBR.  Best Buy offered me a newer Seagate at a slightly lower price but one is claimed explicity to support Linux, and it supports some older protocols.  When I told the people at the store I wanted MBR, not GTP, they just stared at me.
> 
>    The Western Digital drive works.  It just does not work as a boot drive.  I now have an /archive file system.
> 
>    I put my install instructions up on my website in the hopes that I am helping newbies.  I am trying to make sense of all this.  Right now, I figure if you have an old computer with an old hard drive that works, you should be able to install Linux.  If you have a new (GTP) system that works, you should be able to intall Linux on it.  If you have an old clunker and the hard drive dies, look out!
> 
>    Is this a Seagate versus Western Digital issue, or is my WD drive flakey?  Can anybody make sense of all this?  I would like to write this up as a useful document.  

Usually when you buy a disk it is blank.  Totally completely blank.
It has no partition table, no partitionts, no filesystems.  This explains
why the store would look at you like you are nuts.  Disks don't come
with partition tables in general.  External drives might come preformated
and ready to use, but not internal drives.

Whatever you plug it into first may take care of it for you.  If it is
larger than 2TB to use the full size you must use GPT, so many things
default to that.  Maybe the seagate is just under 2TB and the WD just
over 2TB.

Now it is possible to boot from a drive with GPT (not GTP) with an
older bios using grub.  To do it you have to create a GPT partition at
the start of the disk of type "BIOS boot partition".  This is where grub
will place itself and point the MBR boot block at.

You can't boot windows from it, but you can boot linux that way.

Certainly the installer for Debian and Ubuntu support this.  Maybe fedora
doesn't.

-- 
Len Sorensen