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Fedora Core Doesn't Like to Dual Boot?
schwatoo writes "It seems Fedora Core doesn't like to boot alongside Windows 2K or XP. According to a bug first reported in February on Fedora's bugzilla site it has a tendency to chew up partition maps making it impossible to dual boot into Windows. No one seems to know quite what is causing the problem and a lot of people are ending up with unbootable machines."
1. Partition in an older, safe system. E.g. knoppix.
2. Install grub in an older, safe system. You should have grub installed already, if you have been using Linux on the machine previously. I never install bootloader anymore, I've been using the same one forever. Just edit the grub config to point to new kernel & root system.
3. Grub should be on the beginning of small boot partition. Never on MBR, if you can avoid it. Always create a 80MB or so partition on the start of every disk, even if you don't plan on using it (yet). This also applies to secondary disks. Kernels should always go to these partitions.
Save your wrists today - switch to Dvorak
Copy and paste from here
It turns out that the bug (#115980) is a result of a few subtle but key changes within the 2.6 kernel. A certain functionality with regards to hard disk geometry has been pulled out, as the kernel developers thought it would be better if userspace utilities took care of this instead. The Bugzilla bug is related to CHS geometry problems, which most likely stems from an error within the parted utility, addressing the BIOS incorrectly. It turns out that BIOS updates tend to fix problems for many users that have been bitten by this "bug". On newer machines, this is basically non-reproducible.
Mandrake 10.0 Official also suffers from this problem. This is leading many to believe that it is an issue with the 2.6 kernel, rather than a specific distro.
well it was first reported in Feb so oviously they are in no great hurry to fix it.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
Had you bothered to understand my post, you would have seen that I acknowledge that Fedora "messes with the partition table". However, it does so by correcting a technically-invalid-but-working one to a technically-valid-and-working-for-everything-but-X P one.
Let's hope that there's intelligent life somewhere out in space 'Cause there's bugger-all down here on Earth.
The windows boot loader searches a file called boot.ini, inside it, it contains disk and partition numbers.
Since you swapped your HD's around, the disk #'s are now different, therefore it won't boot.
As you'll have seen from various other comments; Mandrake 10 has the same problem therefore if you're using M10 without problems then FC2 will work just as well.
----- Documentation is worth it just to be able to answer all your mail with 'RTFM' - Alan Cox.
I hate to rain on people's parades, but if you're making a system dual-boot with Windows, the conservative/safe thing to do is NOT install a bootloader.
Just use the one that comes with NT/XP. Of course it is limited in features (esp. compared to GRUB) but it works.
It's not a ton of work either:
Write a LILO bootloader to a partition, use 'dd' to copy that to a file (floppy helps), copy the "file" to Windows, and edit boot.ini to point to it.
Sure, it's not automated, but we're talking just a few steps, and then your're 100% confident that the next upgrade of Windows will not choke.
It would be nice if the PC industry could get "all OS vendors" to agree to universal bootloader, and maybe even get it in the BIOS, but the situation is what it is. You've got to be very careful when dual booting, especially with BETA software.
Sounds like the GRUB and kernel people need to work closer together. I don't know about GRUB, but the kernel has some pretty good testsuites so I am surprised this was not caught by the Linux Test Project (LTP). I'm hearing it's actually a 2.6 kernel problem, and since not a lot of people have upgraded to 2.6 we're hearing about it now.
I recently installed Fedora Core 2 on a computer alongside Windows 2000 and had no trouble dual booting. That particular bug has been seen more often with the Test releases of Fedora Core, as should be expected. If it does happen to you, the problem can be easily fixed by running fixmbr in Recovery Console for 2000/XP.
Some people were guessing the problem is due to the 2.6 kernel reporting a different geometry from 2.4 and the tools not being updated to correct for this. I know that even though I didn't repartition, after installing FC2 over my FC1 installation the start and end cylinders reported by fdisk -l are completely different.
Right, I was hit by this. I'm a linux newbie. But I solved it.
/dev/hda | sfdisk --no-reread -H255 /dev/hda"
./sfdisk to make it work. In my case, i had to add the -force flag to the right hand side of the pipe.
:)
To fix it:
-If you don't already have it, get and install sfdisk (there are RPMs out there, no deps)
Run (presuming your hdd is hda) as root "sfdisk -d
You may have to cd to sbin and replace sfdisk with
That command ran, and then i could run WinXP from Grub just fine
However, FC2 has many other major bugs that I and others have found:
- Nvidia drivers don't work (i know it's nvidia's fault, but it's a stumbling block)
- As Xorg is in use, ATI drivers are a bitch to install (although if you use google there is a very good howto out there).
- The kludge i had to use to get software mixing working (dmix under alsa) was inexcusable. With alsa in 2.6, you'd think by default you'd have software mixing. An OS where I can't listen to XMMS and hear GAIM alerts at the same time is just ludicrous. Even sillier is the fact that GAIM alerts are queued, so when i close XMMS i get a minute solid of notification noises playing. Simultaneous sounds SHOULD work out of the box. Esound and arts are not in the equation any more, as alsa mixing is a much better solution - so why isn't it implemented?
- Totem just won't work. G-Streamer broke totally shortly afterwards.
- There's no easy way to edit your applications menu, without either SUing, or logging in as root. This seems daft for a multiuser OS like linux.
I know these bugs aren't Fedora only, but they need addressing if Fedora wants to remain OS of choice for many.
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Seperate disks doesn't matter with this issue, I had XP on hda and installed FC2-test2 on hdb and this bug still bit me. If you install in a work enviornment you definatly should NOT dual boot but if you do there is a safe way of tricking the hard drives into thinking they are both hda and not touching the other. Learn about it here It doesn't work for everyone but if it does, problems like this wont happen again.
-- "of course thats just my opinion, I could be wrong." --Dennis Miller
The solution is to modify Boot.ini in order to update the pointers to the Windows directory. You can either modify the raw references to the disk and partition number, or change it to a Dos-style path of "C:\WINDOWS". If you really wanted to, you can even run install multiple copies of Windows XP on the same partition (with features such as System Restore being considered unstable.)
As you should know, Bootstrapping requires an absolute path pointing to an application, even on Linux. If the absolute path on the hard drive changes, the absolute path given in or to the Bootstrap must be changed as well.
No, they assumed that everybody would not change partitions or hard drives around after the Windows XP installation. This is a fairly reasonable assumption, since modifing partition tables or hard drive configurations implies that you know how to restore operating systems to a workable state if something messes up.
It's also why you see warnings with reparitioning software to backup your harddrive. If something breaks and you don't know how to fix it, then you have something to fall back to.
From what I remember, not only was Firewire unstable in time for release, but was causing instability even for people without Firewire. I'd rather they held off on including it until it is stable rather than risk data loss by including it prematurely.
Ita erat quando hic adveni.
sfdisk -d /dev/hda | sfdisk --no-reread -H255 /dev/hda
(I may have needed a --force in there as well). After that, I was able to set the mode back to "Auto" and both Windows XP and FC2 would boot. Note that all I did though, was basically just recreate my partition table by dumping the info provided by sfdisk and piping it back in sfdisk.
One explanation I read is that the Anaconda screws up the CHS values in the partition table. Windows uses both CHS and LBA, and so when it reads the CHS values it cannot boot. However setting the mode to LBA manually in the BIOS forces Windows to read the LBA values. Linux only uses LBA, so it doesn't matter what mode your hd is set to in the BIOS.
Of course, I don't really know what I'm talking about, but if someone could provide a better explanation...
Actually, that's precisely what it is. 2.6 reports a different layout (typically 16 cylinders instead of, say 255 in the logical one) and grub sets itself up this way. Next, it appears that even when the BIOS was explicitly instructed to use LBA access, this is somehow overriden by GRUB, with the result that trying to launch the NT bootloader fails.
The sfdisk solution on Fedora's bugzilla fails when sfdisk figures a partition does not start at the right cylinder boundary. Apparently, one can try to change the head count only for the windows boot partition, with the hope that it fixes the boot-through-grub problem (I am yet to try this). I guess the biggest problem is for people who don't have an LBA option in BIOS.
As a proof that it's not Fedora-related, I have the same problem with mdk10.
Finally, there seems to be no problem if one sets up the installer's kernel to use LBA access for the hd (no switching to CHS occurs).
Actually it affected me with my 30GB drive as well. Fixmbr didn't seem to work, but recreating the partition table using sfdisk did seem to work:
sfdisk -d /dev/hda | sfdisk --no-reread -H255 /dev/hda
Win2K introduced "dynamic" disks, which changed how the partition table worked. Partition type 0x42 means the disk is dynamic and the real information is contained at the end of the disk. 0x42 is supposed to be a container partition meant to span the disk and say "don't mess with me". An exception are boot and/or system partitions, as those have to be read early during boot before the dynamic disk stuff is loaded. Thus, boot/system partitions can be type 0x42 but not span the disk.
Anyway, as a wild-assed guess I'd check that out. Perhaps lilo/grub doesn't play well with dynamic disks.
This is Linux kernel 2.6 - Mandrake 10, Suse 9.1 and Fedora Core 2 all suffer from this problem.
Switching to Debian won't help if you want Linux kernel 2.6. Your paritition table will be fubared.
Furthermore, people do know what's causing the problem. The Linux kernel now doesn't show the same disk geometry as the BIOS does. The fix is to use sfdisk to recreate the partition table.
The fix is here.
The VIA C3 problem didn't get caught because it worked in the betas. The bug involved is in all the 2.6.x kernels but depends on the alignment and size of the kernel. While the beta kernel worked the final kernel didnt get lucky.
Ingo and others are currently working through this one to try and find the cause. At the moment nobody is sure if it is a Linux bug or a CPU errata being tripped.