Re: [rhil] boot loader

[Rick Stevens <rstevens vitalstream com>]

Vir Calimlim wrote:
> perfect Rick! further on ...
>
> the boot menu shows the following options:
> - RHL 2.4.20-8BOOT
> - RHL 2.4.20-24.9
> - RHL 2.4.20-8
>
> do they represent minimum-maximum-middle startup configuration respectively?
> in what occasions/conditions is it recommended to start one and not the
> other?

No, those are other kernels you can boot.  The latest is 2.4.20-24.9 and
is the one you should boot.  The others are older kernels.  The -8BOOT
is the kernel used by the installer, 20-8 is the first normal RH9 kernel
that was installed on your system.

> its the first time i got to see this menu. am i right to presume that RHL
> 2.4.20-24.9 is supposed to be the only option that should appear there and
> that the other 2 were only added after i played around with install-upgrade?

That's correct.  The update process simply adds the newer kernel to the
menu, but leaves the default kernel alone.  This allows you to boot the
new kernel and try it out.  If it poops out, you can reboot and continue
to run your old kernel.  Once you decide you don't need the other
kernels, you can edit your boot configuration and remove them.  That's
done by editing /boot/grub/grub.conf and removing the other entries.

If the new kernel works, you can edit the config file and change the
"default=" number to point at the new kernel's number in the list (they
start at zero).  For example:
default=1
timeout=10
splashimage=(hd0,0)/boot/grub/splash.xpm.gz
title Red Hat Linux (2.4.20-24.9)
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-24.9 ro root=/dev/hda1 hdd=ide-scsi
        initrd /boot/initrd-2.4.20-24.9.img
title Red Hat Linux (2.4.20-20.9)
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-20.9 ro root=/dev/hda1 hdd=ide-scsi
        initrd /boot/initrd-2.4.20-20.9.img
title Red Hat Linux (2.4.20-19.9)
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-19.9 ro root=LABEL=/ hdd=ide-scsi
        initrd /boot/initrd-2.4.20-19.9.img
title Red Hat Linux (2.4.20-8)
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-8 ro root=LABEL=/ hdd=ide-scsi
        initrd /boot/initrd-2.4.20-8.img

tells grub that the second kernel (following "title Red Hat Linux
(2.4.20-20.9)") is the default kernel, so if you don't select another
one manually, boot that one.  If I changed that to "default=0", then
the first kernel ("title Red Hat Linux (2.4.20-24.9)") would get
booted.

To delete kernels from the menu, delete the "title" line and everything
after it up to the next "title" line, and don't forget to change the
"default=" line, too.  If you want to remove the kernels themselves,
that's a bit more difficult and I can help you if you need it.

> --- From: "Rick Stevens" <rstevens vitalstream com>
> Uh, I think you mean /dev/hda and /dev/hdb, right?  If you want grub to
> install in the MBR of the first drive, first make sure that your
> /boot/grub/grub.conf file is set up correctly, then:
>
> grub-install /dev/hda
>
> --- Vir Calimlim wrote:
> hello gurus! i've got M$ in /deva and RHL9 in /devb. when i first installed
> RHL9, i installed GRUB in the 1st sector of the boot partition which i
> presume is in /deva. the boot loader isn't working so i'm planning to move
> it to the MBR. how can i do this without having to reinstall RHL9? i've
> tried RHL9 upgrade but the boot loader step is not performed giving the
> reason of something about the kernel not being included in the upgrade.

----------------------------------------------------------------------
- Rick Stevens, Senior Systems Engineer     rstevens vitalstream com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
-     There are only 10 kinds of people in the world -- those who    -
-                 understand binary and those who don't              -
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