(SOLVED) Grub - what changes do I make when I remove one drive?

[besonian]

I'm sure that somewhere this has been dealt with, most probably by OP. Even so, I can't find any reference to my specific question. Which is - what changes do I need to make to Grub in order for the OS to boot OK after I've removed one of two drives? - not the boot drive, by the way.

A few weeks back I needed to add a much larger drive to a machine with a KDE4 (all up-to-date) install on it. The original drive was a small and ageing 80gb PATA. So I decided to re-install the OS on the new drive (250gb SATA) - along with new swap and new home. That went fine. I retained the old drive on the system, copied the contents of my old /home directory to the new /home directory and all has been going OK. I did not thereafter remove the old drive. There seemed no reason to do so. Except if I'd though a bit more about it I guess I would have done - I did the re-install on the new drive because I was concerned about the age and condition of the old one. The same considerations, it now seems to me, apply here and I should get rid of it, especially as when I booted this morning I got a message telling me that I needed to run fsck manually because of a corrupted file system on that drive. I did that from a live CD and it then booted OK. But it had to fix no end of problems - asking my permission as it did so - so I reckon when I boot tomorrow the same thing could well happen and the drive's on the way out.

I should know much more about grub than I do. And I should know the answer to this - but all I know is that if I just take the old and now unused drive out, Grub is going to spit at me and refuse to boot the OS. Or is it? And if it is, what changes do I make to Grub to make it behave nicely?

[Old-Polack]

I'm sure that somewhere this has been dealt with, most probably by OP. Even so, I can't find any reference to my specific question. Which is - what changes do I need to make to Grub in order for the OS to boot OK after I've removed one of two drives? - not the boot drive, by the way.

A few weeks back I needed to add a much larger drive to a machine with a KDE4 (all up-to-date) install on it. The original drive was a small and ageing 80gb PATA. So I decided to re-install the OS on the new drive (250gb SATA) - along with new swap and new home. That went fine. I retained the old drive on the system, copied the contents of my old /home directory to the new /home directory and all has been going OK. I did not thereafter remove the old drive. There seemed no reason to do so. Except if I'd though a bit more about it I guess I would have done - I did the re-install on the new drive because I was concerned about the age and condition of the old one. The same considerations, it now seems to me, apply here and I should get rid of it, especially as when I booted this morning I got a message telling me that I needed to run fsck manually because of a corrupted file system on that drive. I did that from a live CD and it then booted OK. But it had to fix no end of problems - asking my permission as it did so - so I reckon when I boot tomorrow the same thing could well happen and the drive's on the way out.

I should know much more about grub than I do. And I should know the answer to this - but all I know is that if I just take the old and now unused drive out, Grub is going to spit at me and refuse to boot the OS. Or is it? And if it is, what changes do I make to Grub to make it behave nicely?

If grub is installed in the MBR of the SATA drive, and that drive is the boot drive, removing the 80 GB drive will have no affect at all on the current OS. If the 80 GB drive is not damaged, and still usable, rather than remove it, you could repartition it to a single partition, format it with a Linux file system, and use it as a data partition.

[besonian]

Thank you, OP. I guessed you'd be somewhere around. To be honest I had a feeling that would be the answer but didn't want to expose my ignorance if I turned out to be wrong. Sad, what?

As for holding onto the PATA drive - that would be my option, so long as it's not on the way up the pictures, which I suspect is where it's headed. I'll keep it for the moment and see if booting goes OK tomorrow. If so, I will, as you suggest, re-partition it and use it as data storage. If however it falls over again tomorrow I'll take it out, put it in a test machine and run a full read/write test on it to see if it's worth hanging onto or not. 

Anyway, many thanks once again.