DANGER!!! Problems with 10.04 installer (RAID devices *will* get corrupted)

[Dave Howorth]

Alvin Thompson wrote:
> On 04/22/2010 07:04 AM, Dave Howorth wrote:
>> I hesitate to join this thread, since it can get a bit heated. But I
>> think that there are probably two separate bugs and I'd like to explain why.
>>
>> #191119 sounds like a problem I have had with a different distro and
>> different hardware config and different partitioning. Basically what
>> happens is that grub overwrites blocks that it shouldn't. In my case it
>> is a true hardware RAID with LVM occupying the whole disk (i.e. not in a
>> partition and I now know why this is not recommended! ). The LVM
>> metadata occupies the start of the RAID virtual disk. grub got confused
>> about the boot order of the machine and wrote to that disk instead of
>> the separate boot disk. #191119 sounds like the same situation, with
>> grub writing to one of the disks in the fakeRAID (and I assume, but
>> don't know, that the fakeRAID has control information at the start of
>> the disk). So that bug would be down to the well-known difficulties grub
>> sometimes has in its relationship with the BIOS.
> 
> The reporter specifically mentioned that he chose a manual install and 
> did not create any logical volumes, so this isn't the same issue.

You didn't think about what I wrote. The LVM is irrelevant. What I'm
saying is that my issue was caused by grub and I think there's a
possibility that #191119 is too. OTOH, I don't think it seems like your
problem is and it therefore seems a sensible precaution to leave the two
bug reports in place for separate investigation.

Until at least one of the problems is bottomed out so both the cause is
known (specific lines of code) and a fix is in place, nobody can be
absolutely sure they are the same bug.

Cheers, Dave