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I have a remotely managed RapsBerry Pi 2 B on the same LAN (different room and floor) without screen, mouse nor keyboard but RJ45 ethernet connected.
I would like to install multiple operating systems, for example Ubuntu Linux and Kali Linux would be enough.
But I can not go to the RapsBerry room when wanting to change operating system, so I would need any method to remotely order boot changing to another one.
In Desktop computers this is easily solved by installing GRUB and issuing the
grub reboot command. Something like:
$ sudo grub-reboot 2
... to boot the third (the first one is the 0) operating system in the GRUB's list.
Is there any not-too-complex equivalent method?
Scriptable solutions (command-line) preferred instead of GUI methods.
Manual file-renaming, moving, editing or equivalent accepted.