On Tue, 23 Feb 2010 at 3:38pm, Khusro Jaleel wrote
Now, after a few months I forgot all about the Ubuntu LiveCD and tried to setup server "B" using the CentOS 5.3 x86_64 CD. However the installer immediately complained that "this disk in using a GPT partition table and this computer cannot boot using GPT" and it keeps saying this no matter what I do. I've tried creating a separate /boot partition, using LVMs for everything, etc but nothing works, even "dd" did not give me much luck, although perhaps I should try deleting the "end" of the disk rather than the beginning?
There are 2 facts at play here:
1) Any device larger than 2TB must use a GPT disklabel.
2) You cannot boot from a device with a GPT disklabel.
None of the tricks you mention above will work. What you need to do is use the RAID card BIOS to divide the array into multiple devices. Most decent RAID cards will either "auto-carve" arrays into <2TB chunks or let you create a small "boot-drive". The latter is preferable, IMO. If your RAID card doesn't offer such an option, then you'll need to either remove some disks from the array to use as boot drives or add more drives to the system.
The additional mystery is that if I check server "A" which I partitioned a few months ago using Ubuntu, the "label" type is "msdos"!! How is that possible? In addition if I use the CentOS CD and try to use parted on server "A" now, it gives the following error:
Weird things happen when trying to boot from GPT labeled devices, including all sorts of data-loss scenarios.