[dm-devel] Re: grub 0.96 bug

[Molle Bestefich]

>> Thanks for the explanation!
>> There should be an option in the GRUB configuration to do this, so
>> that the RAID won't get overwritten the next time I do a grub-install,
>> I think.
> 
> That would make my life a lot easier! On the other hand, the most
> straight forward thing to do would be to move the stage 1.5 to another
> default sector. So you can not forget to set any option that ruins your
> array if missing. Also there is no need to add some autodetection code
> for hpt controllers then.

One step ahead of me, you are.

I was just thinking of doing autodetection of HPT magic in GRUB.

The autodetection has a plus side too, though.
It can detect other stuff that should not be touched (Windows/Veritas
dynamic partition information comes to mind?) and not touch sectors
based on what is actually there on a particular system.  Would perhaps
save the implementor the pain of choosing once there's just too many
reserved sectors and the stage1.5 loader wont fit.

I think I've read that the stage1.5 loader is not really necessary in
some cases, think I'll go doc-hunting.

>> Or even better, dmraid could protect the metadata blocks by some magic
>> flag to dm-mod.
>> This isn't possible as is, is it?
> 
> One can make any I/O to this block fail. But I would like something like
> discarding any writes and only perform reads. "dd" backups would still
> work then.

Right.  And perhaps a user-definable flag to turn the protection on or off :-).
Is it possible without adding new code to dm-mod?