[lug] GRUB2 Compatibility: Mostly Fedora/Ubuntu, Some BIOS/UEFI

[stimits at comcast.net]

...
> A couple of shoot from the hip thoughts:
>
>Just to make sure I understand, you've got a UEFI system running in legacy BIOS mode which worked well for your MBR >partitioned disks on older OSes but after upgrading it's not working so well? The compatibility issues between UEFI, MBR, BIOS, >and GPT mostly come down to how the bootstrapping process loads the kernel from a specific part of the disk. The UEFI/BIOS >issue typically comes down to motherboard firmware interaction with the OS. 
 
I have multiple disks on this system. So far as I know no motherboard supports both BIOS legacy and UEFI modes simultaneously on a per-disk basis. My motherboard definitely doesn't, though it is actually a modern motherboard (it replaced a failed motherboard and is a different model, but uses the same exact CPU/video/etc). In particular Windows 7 does not like changes and requires me to call in to MS and beg for mercy for any change. I'm not even sure this version of Windows supports UEFI, though probably it does...but the re-install part may cause me to lose it.
 
>
>I believe that legacy mode for UEFI was so it could play nice with older OSes. It's my understanding that UEFI can still >understand MBR disks (ie. it doesn't require GPT disks like BIOS systems require MBR disks). I assume you've attempted to >disable legacy mode and tried to let it interact with your MBR partitioned disk?
 
There are all kinds of disks involved. It would take an extraordinary amount of effort (and money I don't have) to safely do that. I suspect the only result would be losing a lot to gain a little bit by running Ubuntu...it is important, but not having Ubuntu is more of an "irritation" level and not a show stopper. Being in legacy mode has allowed me to migrate old partitions over a long period of time. I would not mind UEFI mode if it were able to also work with BIOS mode disks at the same time...I could leave my home and windows partitions in BIOS mode and not worry while I upgraded the base operating system to UEFI. Mixing UEFI and BIOS in one system seems to be about as easy as an exact answer to division by zero (without calculus). UEFI does fail with BIOS legacy mode gone...there is no UEFI partition set up for windows or the several Linux systems.
 
>
>Otherwise, if it's easy (ha, famous last words), you could look at converting your MBR disk to GPT, running your system in >"native" UEFI mode and trying to boot your newly converted GPT disk. Maybe clone your disk before attempting that!
>
>If those things don't help, could we see your partition table?
>-Dan

 
I have a few terabytes of things I'd need to back up and have no means to do. It is financially not possible. I don't think having the one piece of software work under Ubuntu is worth it. I would not have even experimented with moving partitions around earlier if I could have just added another hard drive.
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