Say I wished to have Debian Squeeze and Arch Linux ARM on my SD card. Would it be possible to dual boot from Grub?
While it is possible to put multiple operating systems on the SD card, there is no boot manager at the moment that runs on the Pi and can handle switching operating systems at runtime.
What you could do though, is to have a shell script, located in
/boot, that sets which operating system you want to use on the next boot.
You could accomplish this by storing the boot files for different operating systems in another directory, like so.
Note: The needed files that have to be copied are
Then have your shell script copy the files from the appropriate directory and into
/boot. That way, when you restart it boots into the desired operating system.
Berryboot is essentially a boot loader designed specifically for the Raspberry Pi that will accomplish this for you:
Berryboot is a simple boot selection screen, allowing you to put multiple Linux distribution on a single SD card. In addition it allows you to put the operating system files on an external USB hard drive instead of on the SD card itself.
u-boot(which is used by berry-boot behind the scenes), it is possible to switch between any installed distros to boot at runtime, either using something like askenv for switching between OS's on the same SD or possibly nfs server or with
PXE using a different installation on a
PXE boot server, though it isn't the most trivial thing to get running. I will try to prepare a tutorial.