Installing GRUB after removing HDD

[rks171]

You didn't say what kind of drive sda was, is it SATA?

sda is SATA, sdb is IDE

You didn't say what the mount points of sda[567] are.

sda5 is /
sda6 is swap
sda7 is /home

I didn't create a partition for /boot. Sources I checked didn't list it as necessary and it wasn't mentioned in another installation thread I was talking in.

mount /dev/sda5 /media/root
mount /dev/sda6 /media/root/boot
grub-install blah blah...
grub-install --root-directory=/media/root /dev/sda

I took these steps except I didn't mount /boot since I don't have a separate partition for it. Do I need to mount the /boot directory or something?

Seems to me to indicate that you've put the Grub boot code for sda onto a high partition rather than in the MBR.

Yes, this is certainly the case. I remember checking off MBR during install, but it must have put it in MBR of sdb instead of sda. As previously discussed, I tried to reinstall grub on sda with sdb disconnected, but I get the same error. I believe I'll try ken_yap's suggestion of installing grub to /dev/sda instead of any particular partition and see what that does.

[ken_yap]

Let us know how it goes.

[rks171]

Just tried it this evening and nothing. Same error about GRUB being over the maximum number of cylinders on the HDD. What exactly is the MBR? Is it a special spot with space set aside?

I'm thinking when I run the grub-install it must be doing something to the MBR because the windows boot loader is no longer there. I get the error instead of windows starting right up. But something must also be going on elsewhere on the HDD if the error is about being above a max cylinder.

[ken_yap]

MBR is the first sector of the disk, which also contains the partition table. Also the first track of the disk is reserved for bootloaders. This initial GRUB code loads the stage2 bootloader and after that the kernel and initrd in the /boot directory.

Anything loaded by GRUB has to be reachable by the BIOS because that's all that GRUB has to do disk I/O. On older BIOSes, there is a 128GiB limit due to the size of the arguments to the BIOS I/O calls. It looks like your boot files are beyond this limit. That is why some machines require a /boot partition on the lower cylinders of the disk.

To fix this you need to put the boot files below the 128GiB mark. You may be able to use a gparted rescue to shrink / enough to insert a /boot partition before it and copy the boot files there.

[ken_yap]

Oh there's one more thing worth checking. If the BIOS offers you the choice of native SATA handling or IDE emulation, try the former.

[rks171]

Okay, so the bootloader in the MBR is, in effect, calling to the installation location of GRUB (/boot) and because I have that located on sda5, which is above the 1024 limit, it won't work. So the EISA partition is causing problems. I need to move it out of the way and setup a /boot partition at the beginning of the disk and then install GRUB to that location. I think I have a copy of gparted lying around somewhere, so I'll try to find it and give this a try. I'll fill you in on the results.

[ken_yap]

Not so fast, there are a few odd things about your situation.

The 1024 cylinder (500MB) limit is really old, it is only found on BIOSes older than 15 years or so.

The 128GiB limit is about 10 years old.

Looking at your partition sizes the puzzling thing is that your first Linux partition should be under the 128GiB limit. Also it did manage to load the kernel when the boot sector was on sdb.

So something fishy is going on.

Do you get an interactive GRUB prompt? If so what happens if you do this:

root (hd0,4)
kernel /boot/vm

At this point you can try to do file completion with TAB and see if you get the BIOS limit message.

You can also try to start GRUB from a rescue disk and see if you can interactively load the kernel.

Also did stage 1.5 get loaded, it should say what stages it is loading. And do you still get the reference to (hd1,4)/boot/message?

Another thing is your menu.lst might be wrong. When you had the IDE disk in place, the SATA disk would pushed back to hd1. Now that you have removed the IDE disk, the SATA disk is back at hd0. So all references to hd1 in menu.lst would have to edited to hd0. That would explain the (hd1,4)/boot/message not found.

[rks171]

I'll have to try your suggestions on monday when i'm back in my office. I believe it does load stage 1.5 and then I get the (hd1,4)/boot/message error.

When I used the grub-install... command with liveCD, shouldn't that have created a new /boot/menu.lst that references hd0 instead of hd1 automatically?

[ken_yap]

No, grub-install doesn't touch menu.lst. There would be howls of protest if it did since it contains all the info about what OSes are available. In fact menu.lst can be edited at will any time, that's the advantage of GRUB over LILO.

To be really sure of what GRUB is installing, do the steps by hand from the rescue system, after editing menu.lst:

# grub
grub> device (hd0) /dev/sda
grub> root (hd0,4)
grub> setup (hd0)

At this point you will get messages about embedding various parts of GRUB on the disk.

[rks171]

Bravo, man, that did the trick. I simply opened up menu.lst with vi and changed all the hd1's to hd0's (and two hd0's to hd1's). Shutdown, pulled the IDE hardrive, started it up and GRUB popped right up. No need to reinstall or use the rescue system. Thanks a lot for the clever solution.