On Wed, Jul 30, 2008 at 11:27:22AM -0700, Robert G. Brown wrote: > On Wed, 30 Jul 2008, David Mathog wrote: > > > David Lombard wrote: > > > >> On Wed, Jul 30, 2008 at 09:13:56AM -0700, David Mathog wrote: > >>> It then occurred to me that doing so would > >>> require a trip through the BIOS on every reboot, at least on every x86 > >>> based computer I'm familiar with. > >> > >> Not since kexec was added to the kernel! > > > > That's exactly what I was thinking of for the Beowulf node problem. > > For instance: > > > > http://www.knoppix.net/forum/viewtopic.php?t=27192 > > > >> Beyond using kexec as described above, grub directly supports this; lilo > >> did too. > > > > I know how to do this by changing the configurations, but not how to > > specify a one time change that doesn't need to be manually undone later. > > Is either of these boot loaders capable of doing the logical equivalent of: > > > > grub-next-boot-only -default 3 > > > > (Override whatever default is in the config file, but just for the next > > boot.) > > There are several ways to accomplish this, and they can be automated. > For example, run a script at boot time that runs a script like > /etc/specialboot if it exists. Then put: > > #!/bin/sh > > # cp /boot/grub/grub.conf.default /boot/grub/grub.conf > # cp /boot/grub/grub.conf.special /boot/grub/grub.conf
According the the FM, there's a "grub-set-default" program that does the trick. It supposedly creates a "default" file in the grub directory, nominally /boot, that causes grub to behave differently. That's what I was alluding to in my first post. Sadly, no such program exists in my F7. GIYF teaches us that the new method is: # echo "savedefault --default=2 --once" | grub --batch # reboot where "2" is the choice for your next one-time boot. I haven't tried this; I did use the LILO method when it was the bootloader of choice... -- David N. Lombard, Intel, Irvine, CA I do not speak for Intel Corporation; all comments are strictly my own. _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
