Want to boot GRUB from CDROM or USB drive
 

Here's my challenge. I have had a dual-boot laptop with Windows Vista (now Win 7) and Ubuntu for years. Recently, I decided to create a new partition out of unused space from within Windows. It didn't work right, but I didn't realize it until I rebooted and couldn't access the hard drive. The boot sector had been corrupted.

It had something to do with GRUB2 being the bootloader. A year or so ago I was able to use the original GRUB installed on the Linux root partition and Easy BCD to edit the Windows Vista (later 7) bootloader file, which still leaves Windows doing the chore of the initial boot, then switching to loading GRUB from the Linux root partition.

When I installed the most recent LTS Ubuntu, it came with GRUB2, and I let it install in the MBR since I couldn't get Easy BCD to make the switch at boot time to Linux.

When I made changes to the partitions from within Windows, it corrupted GRUB when Windows tried to write information where GRUB was located.

I got that fixed, and it took a lot of searching for the answers, one of which I had used the first time around so that I wouldn't have lost data between my last backup and when that happened.

I don't feel comfortable putting GRUB back into the hard disk MBR, so I need to find an alternative way to boot to the root Linux partition, whether it's booting from a CDROM or a USB drive just to switch to the hard disk Linux installation.

So since I can't seem to let Windows do the booting to GRUB if it's GRUB2, is there a way to install Ubuntu with the original GRUB during the install process? Or to create an alternative way of booting to Linux?

I thought I'd put this in the newbie forum (even though I'm somewhere further along than that, but by no means an expert!) since it might be good to point out that working with partitions from within Windows when you have GRUB installed in the MBR can cause a serious problem, and that new ones might also want to find a work-around to avoid this problem.

There was something I read about chainloading to GRUB2 but I can't say it was easy enough for me to understand what the discussion was about. Perhaps I'll need to go in that direction. What I don't want to do is use a solution that involves GRUB or GRUB2 in the MBR of the drive. GRUB (original) works OK in the Linux partition. I can get to Linux that way. I haven't considered other Linux loaders like LILO but maybe that would work?

It just dawned on me that it might be possible to access my Ubuntu installation (which I think is still intact) from a live CD somehow, get it running, then install the original GRUB into the root partition. I don't know how to do that, but it might be a way to fix this. I would have to do this every time I upgraded to a new version, though, which is a downside to this if it would work.

I hope I erred on the side of too much information instead of not enough here. :-)

Thanks ahead of time.

Donald

in short yes you can with the orginal grub though i do not know if the orignal grub supports etx4 file system that ubuntu 10.04 uses and im not sure how reinstalling your grub will affect windows.... but if you want to reinstall your grub here
http://ubuntuforums.org/showthread.php?t=224351 and to make it run from a cd or usb Thats a good one i dont even know if thats possible though i would think it would be...

Have a read of this. Cover all that you asked I think.
Supergrubdisk comes with a (very) small image that'll go find grub2 installs - very handy. The Ubuntu one is a bit brain-dead in that it'll only find the first Linux install. Probably o.k. for you, but not if you have more than one (Linux) distro on the hard disk.

You could install grub2 into the partition boot sector record, and try loading that from EasyBCD. I haven't tried it.
Installing grub2 into a partition is usually advised against because it uses a load list (like lilo), and if the files get moved (in the partition) it'll break the boot. Works o.k. for me when I've done it, but I'm careful.

Unfortunately, Easy BCD doesn't play well with GRUB2 in the Linux partition for some reason, while the original GRUB worked fine with EBCD.

I'll check the link in the previous post and yours, too, and see what I can make of it.

Easy BCD now is at a higher version level so they might have worked out the problems with GRUB2. I just downloaded and installed it, but it will be sometime tomorrow at the earliest that I'll try it out, once I have GRUB or GRUB2 installed back in the Linux partition.

I may still have my Linux Mint partitions, but I think I deleted them when I fixed the Windows installation and made another partition for data and files.

Thanks, both of you. Of course, I'll check back when I get a notification that someone else has an idea to try out.


Donald