Bug#764798: grub2: Grub rescue shell with RAID 6 mdadm over 8 disks

[Jeroen Dekkers]

Control: tag -1 moreinfo

Hi Mike,

On Thu, 23 Oct 2014 18:20:00 -0500 "Mike" <ctrlbrk at yahoo.com> wrote:
> Greetings, anything else needed from me?

I don't have VMWare, but tried to reproduce it using KVM (the host
machine is running wheezy). When I configure 10 SATA disks I see all
of them in grub, but when I use VirtIO disks I only see 7 of
them. Turning debugging on and looking further I see that the bios
simply gives an error when trying to access disk 8 and the boot menu
also only shows 7 disks - so in this case the problem is in the bios,
not in grub.

Can you turn on debugging in the grub console using 'set pager=1' and
'set debug=all' and give the output? The debug information from
biosdisk.c is the most interesting. If the problem is that the bios
doesn't support more than 8 disks there is not much we can do except
for documenting it and give a warning for RAID arrays with more than 8
disks.

Kind regards,

Jeroen Dekkers