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I just installed Linux to try to have a Windows/Linux dual boot system, but Grub is getting an error #21 when it loads, so I can't boot into anything.
I tried doing a Ghost restore, but the damn thing doesn't let me restore the MBR! :(
I tried using the Vista startup repair, but it says it can't find anything wrong.
How do I fix my MBR so I can boot back into Windows?
Back in the Windows 2000 & XP days I could run "FDISK /MBR" but I couldn't find fdisk on the Vista DVD.
Did the Linux installer change your active partition? Sometimes, they install grub to the Linux partition and leave your mbr alone. Try changing the boot partition back to C:
I'm not sure what Linux did to my system.
I think it probably has something to do with my ICH9R RAID 5 which Linux sees as 3 separate drives, so it probably installed grub to the MBR of the first hard drive in the RAID set causing the ICH9R BIOS to get totally confused about what's going on.
Anyways, Linux is gone now and I found out that on Vista I need to run bootrec /fixmbr
Hmmm. Here's what you should have done.
The MBR is 512b. Before the install:
dd if=/dev/hda of=mbr.copy bs=512 count=1
Dunno if there is a dos equivalent so you could do this from Windows, anyway, notice that's "hda" not "hda1", etc. You know where it is. Now you copy that to a usb or floppy or something and keep track of it.
To restore to the former state:
dd if=mbr.copy of=/dev/hda bs=512 count=1
You can do this from a cdrom rescue disk, swapping in another hd, etc.
I have done this quite a number of times with both windows and linux. If it was a windows only drive before, restoring the mbr will mean you skip grub and go straight to windows as if linux did not exist.
New linux installs always seem to overwrite the mbr and reference the grub they installed. I am too lazy to figure out how to prevent this for every distro (if it's even possible), but I usually prefer to keep using the grub that's already there and manually add new entries, so I back up the mbr first and then replace the new one afterward.
An MBR is 512 bytes, not kb. But I think you know that, as you do copy the right number of bytes. But just for whoever reads it; the MBR is NOT 512kB but 512B.Quote:
Originally Posted by MK27
Yeah, sorry, will edit that. The dd command was correct (bs = block size and it's in bytes).
Most Linux installers I've used have an option (usually just prior to the final step) that allows you to choose where to install grub, or to not install it at all. You might have to look into advanced options or something, but it's usually available.Quote:
Originally Posted by MK27
I've also installed a couple of distributions that left the mbr alone, and just changed the boot partition to the one where grub was installed. In that case, all you have to do is change the active partition back to what it was previously.
Is there any way to get Linux to insert itself into the list of OS's in the Windows boot loader instead of installing Grub or Lilo, which either loads Linux or goes to the Windows boot loader...? I imagine it would be pretty simple to do.Quote:
Originally Posted by NeonBlack
I also prefer to use Windows's boot loader instead of grub, but there is no way for it to boot Linux directly. So what I do instead is have the Windows boot loader boot grub4dos, which is configured to boot Linux instantly. I find that this works pretty well as long as you don't have more than 1 Linux installation. You can get it to work with multiple Linux installs, but it requires a bit more effort.
Be sure to read the documentation before doing anything:
Grub4dos tutorial - Grub4Dos Wiki
Isn't there a way to get rid of the Windows boot loader (as in the menu), and add one entry for every Windows installation in grub?
I'm pretty sure the Windows boot loader can't boot Linux, though.
Why not? Does it need to do more than go to a certain location of the hard drive and start executing what's there? I would imagine that's how it works, but I know nothing about boot loaders.Quote:
Originally Posted by cyberfish
Either way, I'm not going to try installing Linux on my good machine again. The partition manager thought one of my RAID disks was a Linux swap partition, and I don't trust it enough to not start swapping stuff onto my RAID drive and totally screw up my data.
It needs to go into the filesystem (it has filesystem drivers) and find the right kernel, and pass it the right options to start it.
Unlike Windows, Linux installations can and most do have multiple kernels.
Don't use the installer partition manager, they're all gimpy GUI things to simply things for newbies. Set up the partitions yourself with windows (if possible) or use a cdrom and run fdisk.Quote:
Originally Posted by cpjust
gparted (a frontend to parted) is pretty good. You can launch it from most Live-CDs (I know ubuntu has it).
Sure, but can you guarantee that Linux won't see my RAID drive and say "Oh look, a big swap partition. Lets start using it"?
Nope. That's entirely possible.
I believe by default Live-CDs look for swap partitions and use them automatically.
But why are your RAID partition IDs set to Linux swap in the first place?!
You sound like some whiny brain-dead mouse wielding idiot having a hissy fit. What do you mean by "linux" might see what and start doing what? This is all about the specific tools you are using (and not using) and your ignorance of the system itself.Quote:
Originally Posted by cpjust
Do you really believe there are no RAID arrays in the world that are run fine with this configuration? There's probably tens of thousands of them. More. You are just to lazy to figure it out...you need to get a grip on the partitions as they are seen by fdisk, avoid the stupid mickey mouse distro Live CD one click and I'm finished attitude. Everybody wants everything to work easy for them, or else it is the hammer's fault for not hitting the nail properly.
I can't believe I'm listening to a bonefide programmer alarmed by the fact that a computer is a somewhat complex artifact.
I have no idea. Maybe that's the way the Intel ICH9R RAID chip works internally?Quote:
Originally Posted by cyberfish
I really wish it was a 100% hardware RAID so Linux would actually see the RAID partition instead of 3 separate disks, or at the very least they should make some Linux RAID drivers for the ICH9R.
<Yawn>Quote:
Originally Posted by MK27
<giggle>Quote:
Originally Posted by cpjust