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andygif
7th September 2006, 10:38 AM
hi,

can someone on here give some pointers as to why this process isnt working please.

i have an industrial pc that has a hard disk on it primary ide channel, i do not have access to the physical drive or its cable, but i do have access to the secondary ide channels cable.

i have a hard disk on the secondary cable set to be the boot the system so i can dd the new disk image over the existing disk on the primary ide channel.
the problem comes that the system boots on the secondary disk via the bios and then grub, but when grub carries on it mounts the primary ide disk and not the secondary disk to complete the boot sequence.

the secondary disk is showing up as /dev/hdc and in grubs device map it shows as (hd0) /dev/hdc and grub is set to us a root (hd0,0).

why is it then going on to use the primary ide disk which is /dev/hda and isnt even mentioned in the device map??

how do i get it finish mounting on the secondary disk, ignore the primary disk entirely so i can dd over it.

Cheers
Andy

huw-l
8th September 2006, 01:25 PM
If this PC has a CDROM drive it might just be easier to boot from a rescue disk and do the dd from there.

As to grub, I suspect it's ignoring the device map and assuming the /dev/hda is (hd0). Don't know why though, sorry.

andygif
8th September 2006, 01:38 PM
hmm, thats what i was thinking huw-I, grub is making assumption about the way the internals are structured rather than bothering to check.
No cdrom, or floppy to boot from. There is the option of USB stick but thats going to be pain in the arse getting that to work anyway as it only usb 1.1.
It wouldn't be so bad if the makers of the unit hadn't gone mad with the hot melt glue and stuck everything to everything else to prevent vibration. I dont want to have to specify in the productuion build docs, hack away all the glue so you can unplug the ide cable and plug it in the secondary channel, do the DD and then swap it back and re glue it.
Im looking at shrinking the install and app so it will eventually fit on a decent sized flash card and do away with the burried hard disk altogether. But time and budget will probably mean it never gets done

cheers
Andy