[CentOS] GRUB, and how do I loathe thee

[Gary Greene]

On 6/4/10 3:10 PM, "Dominik Zyla" <gavroche at gavroche.pl> wrote:
> On Fri, Jun 04, 2010 at 03:06:30PM -0700, Gary Greene wrote:
>> On 6/4/10 2:59 PM, "m.roth at 5-cent.us" <m.roth at 5-cent.us> wrote:
>>> Thanks, all, and with the help of the other admin, the system is up. What
>>> I had to do was linux rescue, the chroot /mnt/sysimage, grub-install
>>> /dev/sda
>>> 
>>> What I didn't get until later was it also needed /boot/grub/grub.conf, and
>>> then
>>> ln -s /boot/grub/grub.conf /boot/grub/menu.lst
>>> ln -s /boot/grub/grub.conf /etc/grub.conf
>>> 
>>> and it now boots. As I said, *so* much easier than editing /etc/lilo.conf,
>>> and rerunning lilo....
>>> 
>>>       mark
>>> 
>>> _______________________________________________
>>> CentOS mailing list
>>> CentOS at centos.org
>>> http://lists.centos.org/mailman/listinfo/centos
>> 
>> Mark, you might dislike Grub, but overall, it's saved me a lot of grief
>> since lilo cannot start a "shell" so the poor sod can coerce the system to
>> start another kernel if needed. (Yes, this has happened more than on one
>> occasion with many the distro for me when dealing with rolling my own
>> kernel.) That and lilo is completely useless on newer hardware (EFI and GPT
>> labels anyone?) since it only understands BIOS addresses, whereas GRUB2
>> understands both. As stated in an earlier email in this thread, this is
>> mostly caused by Anaconda and some of the GUI tools doing the wrong thing,
>> not GRUB.
> 
> Lilo is good choice once you're running software raid. It can write MBR
> on all disks and kernel can boot only from one disk with no intervation.
> Grub's writing MBR only at the first disk.

That's a misconception. Grub CAN write to ANY MBR, not just the disk at
0x80. This is trivial to do with grub shell. See the info pages for how.

-- 
Gary L. Greene, Jr.
IT Operations
Minerva Networks, Inc.
Cell:  (650) 704-6633
Phone: (408) 240-1239