Multiple OS booting with grub
Hi, A friend of mine, that I convinced to try SuSE - in fact, we share the cost, thus my interest ;-) - complained that although he told yast to install grub on a floppy, his harddisk boot sequence is altered in such a way that windows does not longer boot. And me been his "local guru" and living at 150 Km distance, I don't have it too easy to check what is happening, nor knowing if he did something wrong. He said that something was written to his mbr and had to use windows "fdisk /mbr". At a second install trial, not even that worked (windows complained of "bad partition table"). In fact, what it happens is that if the floppy is removed, it doesn't start, but it does if he uses the grub menu. On investigation, it seems that grub modifies (clears) the "active" or "bootable" flag from partitions (his normal boot disk is disk is /dev/hdh). That behavior seems to be controlled by the "makeactive" line in "/boot/grub/menu.lst". Can that line be commented out safely? Is it proper for Yast to activate it, when the user requests "boot floppy", because he doesn't want to modify his normal boot sequence? Opinions? -- Cheers, Carlos Robinson
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In fact, what it happens is that if the floppy is removed, it doesn't start, but it does if he uses the grub menu. On investigation, it seems that grub modifies (clears) the "active" or "bootable" flag from partitions (his normal boot disk is disk is /dev/hdh). That behavior seems to be controlled by the "makeactive" line in "/boot/grub/menu.lst".
Can that line be commented out safely? Is it proper for Yast to activate it, when the user requests "boot floppy", because he doesn't want to modify his normal boot sequence? Opinions?
Not sure about the boot floppy but on my system, I do not have that flag in my menu.lst. I'm sure that my partition setup is different and I do not use a bootfloppy. I thought that the M$ partition should be active and setup the PC to boot from a floppy in BIOS. Then the only info needed on the floppy is the info for the Linux partitions. That way when the PC boots, it will find the boot record on the floppy and try to boot from it, bypassing the bootstrap on the HDD. -- Marshall "Nothing is impossible, we just do not have all the anwsers to make the impossible, possible."
The 03.07.02 at 09:12, Marshall Heartley wrote:
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In fact, what it happens is that if the floppy is removed, it doesn't start, but it does if he uses the grub menu. On investigation, it seems that grub modifies (clears) the "active" or "bootable" flag from partitions (his normal boot disk is disk is /dev/hdh). That behavior seems to be controlled by the "makeactive" line in "/boot/grub/menu.lst".
Can that line be commented out safely? Is it proper for Yast to activate it, when the user requests "boot floppy", because he doesn't want to modify his normal boot sequence? Opinions?
Not sure about the boot floppy but on my system, I do not have that flag in my menu.lst.
I have comented out the "makeactive" lines on my menu.lst, and my system is still happy. I suppose it is only necessary when there are two boot partitions on the same disk, so it might be an overkill by Yast to put it always.
I'm sure that my partition setup is different and I do not use a bootfloppy.
Me neither... is my friend who does, he doesn't want to alter his mbr, he want's his windows intact. But I have the custom to install lilo/grub to a floppy the first time on a new computer, just in case. After I know it works, then I move it to the mbr.
I thought that the M$ partition should be active and setup the PC to boot from a floppy in BIOS. Then the only info needed on the floppy is the info for the Linux partitions. That way when the PC boots, it will find the boot record on the floppy and try to boot from it, bypassing the bootstrap on the HDD.
That's right, more or less. A grub/lilo floppy only has the boot sector (well, grub may have a few things more, I'm unsure). But the makeactive line tells grub to make active that partition, and maybe clear it if you boot another system: and that is a problem, yast shouldn't do that in the case of booting from a floppy, or it should ask. -- Cheers, Carlos Robinson
I thought that the M$ partition should be active and setup the PC to boot from a floppy in BIOS. Then the only info needed on the floppy is the info for the Linux partitions. That way when the PC boots, it will find the boot record on the floppy and try to boot from it, bypassing the bootstrap on the HDD.
That's right, more or less. A grub/lilo floppy only has the boot sector (well, grub may have a few things more, I'm unsure). But the makeactive line tells grub to make active that partition, and maybe clear it if you boot another system: and that is a problem, yast shouldn't do that in the case of booting from a floppy, or it should ask.
I agree that it should ask you about that. Not sure why they did not encorporate that feature. More or less? I thought that I hit the nail on the head. Oh well that isn't a issue. Hope that that helped in some way. -- Marshall "Nothing is impossible, we just do not have all the anwsers to make the impossible, possible."
participants (2)
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Carlos E. R. -
Marshall Heartley