I believe that after you boot from the live cd, you can remount the boot 
partition with something like

mount -o rw,remount <device for boot partition>

such as

mount -o rw,remount /dev/sda1

if the boot /boot were on /dev/sda1

and you can just type

mount

to find out where /boot is currently mounted

Good Luck

PS -
   The   "memory for crash kernel ..."   thing is, I think, normal

On 7/26/11 8:58 AM, Rye, Gene R. wrote:
>
> After loading RHEL5 onto a system and then configuring the security in 
> accordance with the NSA Guide, I cannot boot the system.  I am getting 
> the error :
>
>      Memory for crash kernel (0x0 to 0x0) not within permissible range
>
>              Kernel panic - not syncing: VFS: Unable to mount root fs 
> on unknown-block (0,0)
>
> I believe there may be a problem with the /boot/grub/grub.conf file.  
> I can boot the system with a Fedora livecd but am denied access to 
> modify the file.  Any words of help?
>
> Thanks
>
> Gene Rye
>