PSIgroup | Computing / BootloaderToggling

Bootloader toggling was set up to be able to switch between OSs just by rebooting. This enables remote users to switch OS since no interaction is required as the bootloader is running. Linux distributions can somewhat straightforwardly alter bootloader settings, but manipulating the Windows bootloader would be more difficult.

To keep things simple, workstations just toggle back and fore from Windows to Linux on each boot. This can be accomplished from Linux by chainloading the Windows bootloader from grub. The grub-reboot command can be used to temporarily change the default boot entry. After booting the alternate OS, the real default is reinstated.

This can be automated by a systemd oneshot service at /usr/lib/systemd/system/boot-flip.service on the Linux partition:

[Unit]
Description=Flip default boot OS to Windows.

[Service]
Type=oneshot
ExecStart=/usr/sbin/grub-reboot 'Windows Boot Manager (on /dev/nvme0n1p1)'

[Install]
WantedBy=multi-user.target

Check the name grub uses for a boot entry with `grep menu /boot/grub/grub.cfg` and edit the ExecStart line accordingly.

This set up is currently in place on the Bhubesi machine.