Re: install-mbr on amd64?
Alexander Sieck <alexander.sieck@web.de> writes:
> After running 'grub-install' on /dev/sdb, both MBRs, on /dev/sda
> and /dev/sdb, contain the right data.
Some data but the right data? The two MBRs should be identical or not?
Have you tried removing sda and boot or swap sda and sdb around and
boot? (below I see you haven't fully tested that)
> # BEGIN-CLI
> deb64a:~# grub-install --root-directory=/boot --no-floppy /dev/sdb
> Probing devices to guess BIOS drives. This may take a long time.
> Installation finished. No error reported.
> This is the contents of the device map /boot/boot/grub/device.map.
> Check if this is correct or not. If any of the lines is incorrect,
> fix it and re-run the script `grub-install'.
>
> (hd0) /dev/sda
> (hd1) /dev/sdb
>
Lets interleave the data for comparision:
> deb64a:~# dd if=/dev/sda bs=512 count=1 | od -v | head -n 12
> deb64a:~# dd if=/dev/sdb bs=512 count=1 | od -v | head -n 12
> 0000000 044353 150220 000274 175574 003520 017520 137374 076033
> 0000000 044353 010220 150216 000274 134260 000000 154216 140216
> 0000020 015677 050006 134527 000745 122363 136713 003676 002261
> 0000020 137373 076000 000277 134406 001000 122363 020752 000006
> 0000040 067070 076000 072411 101423 010305 172342 014315 172613
> 0000040 137000 003676 002070 005565 143203 100420 177376 072407
> 0000060 143203 044420 014564 026070 173164 132640 132007 001003
> 0000060 165763 132026 130002 135401 076000 100262 072212 001003
> 0000100 000201 020000 000001 000000 001000 110372 173220 100302
> 0000100 000377 020000 000001 000000 001000 100372 100312 051752
> 0000120 000174 030400 107300 107330 136320 020000 120373 076100
> 0000120 001165 100262 054752 000174 030400 107300 107330 136320
> 0000140 020000 120373 076100 177474 001164 141210 137122 076577
> 0000140 177474 001164 141210 137122 076571 032350 173001 100302
> 0000160 032350 173001 100302 052164 040664 125273 146525 055023
> 0000160 052164 040664 125273 146525 055023 071122 100511 052773
> 0000200 071122 100511 052773 072652 120103 076101 140204 002565
> 0000200 072652 120103 076101 140204 002565 160603 072001 063067
> 0000220 046213 137020 076005 042306 000777 105546 042036 143574
> 0000220 160603 072001 063067 046213 137020 076005 042306 000777
> 0000240 010004 143400 001104 000001 104546 004134 042307 000006
> 0000240 105546 042036 143574 010004 143400 001104 000001 104546
> 0000260 004134 042307 000006 063160 140061 042211 063004 042211
> 0000260 063160 140061 042211 063004 042211 132014 146502 071023
> # END-CLI
>
> I did not unplug or replugged the HDs, but I changed the
> HD boot order in the BIOS, from IDE-channel2, -channel3 to
> IDE-channel3, -channel2, and can boot in both cases.
Is that the same as removing a disk or does that preserve sda as hd0
and sdb as hd1 and just boot from hd1?
> I think this prooves that grub does not work out of the box
> with RAID1 as many might expect, but that it is quite easy
> to enable booting from both HDs.
It is rudimentary but needs improving imho.
> Even if the MBR is missing on the 2nd drive and the
> 1st drive crashes, one can still install the MBR on the
> 2nd drive with a rescue CD.
Unfortunately every time you run into such a problem you just can't
seem to find that rescue CD. :(
> Alexander
MfG
Goswin
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