Stewart Nelson wrote:
I have a conventional dual-boot system: Win XP on IDE primary master, grub in MBR, FC2 on primary slave.
If either Windows or FC2 is running, I can access it with VNC. Of course, a reboot will switch to the default OS, if the other is running. However, I don't know how to switch back.
Is there a good way to boot FC2 from Windows? Or to boot Windows from FC2?
Here is how I would do it. I would make my linux be the default OS to boot into. You mentioned that you can control both OS'es remotely so this shouldn't be a problem. If you are in windows, then you can just reboot to boot into linux. While in linux, you can reboot into windows by executing the following commands:
enter grub with:
grub --no-floppy (don't probe floppy drives makes it go faster if you do not have a drive like all my machines)
in the grub command line:
savedefault --default=2 --once (replace 2 with the appropriate selection that is your windows option in grub.conf)
quit
Then you can reboot and it will boot into Windows. When you reboot again, it will go back into Linux.
The way I do it is to have the XP bootloader in the MBR, and have it chain-load grub to boot Linux. The first partition on the first disk is a small FAT partition that contains XP's boot.ini file. By manipulating this file (which, since it's on a filesystem that can be both read and written from both XP and Linux, can be done from either OS), I can choose which OS to boot by default and hence, what will get booted if I just reboot.
The key to this is having a bootloader configuration file on a filesystem that can be written by all OSes in use. In my case I'm OK because I have a FAT partition at the start of the disk, because I partitioned the disk with this in mind. An alternative approach might be to use ext2fsd (http://ext2fsd.sourceforge.net/), an ext2 filesystem driver for Windows, which could allow you to modify grub.conf from Windows.
Paul.
