[CentOS] Grub boot loader?

Mon Feb 1 09:11:49 UTC 2010
James Hogarth <james.hogarth at gmail.com>

On 1 February 2010 08:33, hadi motamedi <motamedi24 at gmail.com> wrote:
>
>
> On Mon, Feb 1, 2010 at 8:24 AM, MHR <mhullrich at gmail.com> wrote:
>>
>> On Mon, Feb 1, 2010 at 12:04 AM, hadi motamedi <motamedi24 at gmail.com>
>> wrote:
>> > Dear All
>> > On my CentOS server , the '/boot/grub/menu.lst' has the right
>> > configuration
>> > but when I reboot my CentOS server I cannot enter to grub edit menu to
>> > edit
>> > my boot kernel by pressing the 'e' key . Can you please confirm if I can
>> > activate it through issuing the followings :
>> > #grub-install /dev/hdax
>> > Is it a safe procedure to try with? Please confirm.
>> > Thank you
>> >
>>
>> Are you starting with a <space> to interrupt the boot?
>>
>> Have you tried editing it using a normal editor (vi or emacs) as root
>> while the system is up?
>>
>> What exactly are you trying to do?
>>
>> mhr
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>
>
> Thanks for your message . When I reboot my CentOS server I see the the menu
> with a timer but I cannot enter to edit my boot kernel by pressing 'e' key .
> Then the timer will expire and the boot process will begin . I want to be
> able to edit my kernel through grub edit so I asked if I can try for
> 'grub-install /dev/hdax' w/o any harm on my CentOS server . Do you mean I
> can edit my '/boot/grub/menu.lst' by vi the same as I want to do inside my
> grub edit ? Are they the same procedures ? Please confirm.
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>
>

When grub runs it will read /boot/grub/menu.lst to determine it's
configuration. There is no need to run grub-install for a change to
configuration as that just installs the stage 1 boot loader code in
the MBR or partition. ALSO SO FAR AS I recakk (migth be wrong) any
edits done to the configuration via 'e' from the grub menu (which
sounds like what you want to do) are non-persistent and it's more for
debugging and//or booting with a broken configuration... If you can
get into the system itself edit /boot/grub/menu.lst ....

Phew... thankfully we don't have grub2 in centos yet and issues
surrounding module loading and the /etc/grub.d architecture ;)