Re: from dual boot to single boot

mark south wrote:
On Thu, 03 May 2007 15:54:27 +0000, Phil Sherman wrote:

Your only possible option is to see if your BIOS will let you choose which disk drive to boot from. Unfortunately, changing this regularly will be an issue.

Quite flatly incorrect. Also, will probably fail, since Linux generally
doesn't care what your BIOS says about which disk is which, only what the
actual cable setup is.

I have systems where I can specify which PHYSICAL disk should be tried first for booting. If grub/LILO is installed on any other physical disk, the system will never even attempt to load it. Initial booting, at this level, is controlled by the BIOS and it will follow your instructions telling it which disk drive it first attempts to boot from. Unfortunately, changing this requires an update to the BIOS defaults. Most BIOSs have a limited number (a fairly large one) of update cycles for the user parameters until they have significant probability of errors.

Now, there is a simple solution, and the cleanest way to do this is to
have XP entirely installed on either disk, RH entirely on the other, and
use a Smart Boot Manager floppy to choose which disk to boot. (SBM is
also useful for booting from CD on systems that can't boot form CD :-)

I have no idea how this works because I've never used "Smart Boot Manager" but, after looking at the documentation available from Sourceforge, running it from a floppy seems to be the equivalent of building a grub bootable diskette to select which physical disk to boot from using the chainloader option. It appears that SBM would be easier to use because it doesn't have a configuration file to play with and it can also be installed on the first drive that the BIOS attempts to boot from. I suppose it could also be made into a bootable CD for systems that don't have a floppy drive.

I'll keep this in mind if I ever need that type of solution to a boot from which drive issue - thanks.


Phil Sherman

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