My Problem: I was fooling around with grub lately and tried to boot Linux from an onboard raid. Searching for a kernel with find /boot/vmlinuz gave me (hd0,7). Nice so far but when I translated it to /dev/hda7 to use as the root parameter it stopped with a kernel panic. Could not find root partition. Clear to me cause the root partition is on /dev/ataraid/d0p8.

Now my question: Is there a way that grub can tell me the true device mapping under linux? Or tell me that we are using a raid system?

grub counts from zero so hd0,7 = partition 8 and then if that is all you did you have to know if you have an ide or scsi or sata to translate to hd or sd.

2) but you could have set root to your / partition and used find /etc/fstab to get the info as per my troubleshooter

3) no bootloader that I know of ....gives verbose message that you are on a raid or non-raid system


4) ideally raid is a trick so the bootloader should not notice in any case.....raid is either used for speed so striping...or redundancy so mirrored...and is for business or mission critical stuff....if you have a normal desktop a cd/dvd burner will suffice so you could just look at raid stripes for speed?

thanks for the reply,

the find advice is very useful to see if one has hd or sd. But I'm not getting it what you mean with point four.

Just for completnes. I have to put a line like

kernel /boot/vmlinuz root=/dev/ataraid/d0p8

to start my system. If i use /dev/hda8 the kernel can't mount the root partition.

Just one more stupid question. Is it possible to have grub print out a file? Would be nice to have the /etc/fstab file to be printed on the screen. Don't think so but it would be a nice feature.

point 4 is my feeble attempt to explain why some people use raid.....either for speed or in case of disk failure.

Not aware of any print function except to screen.

I do not use software or any raid so can not help with your stanza but if it works for you ....well done

Would be nice to have a feature that would print out at least /etc/fstab. With that one could start up a broken system without any prior knowlegde of geometry and no need for a live cd.

I think it should not be that hard to include into grub 2.*. Grub as far as i know can reread a configfile. And from there it should not be hard to print on the screen.

I think I drop a line to the developers and see what they say.

Cheers

ummm it can already display /etc/fstab to screen.

see the troubleshooter to see how to use the tab and find

That's the bomb!!

Thanks for pointing that out to me. GRub is the best. You can just carry a grub bootdisk and get nearly every system up and running without knowing anything about its hd geometry, by just catting its /etc/fstab file.

I think I will browse your two links a bit more to realy get the hang of grub. I need to check on that bootchain thing.

Cheers Zhjim