I'm finding that
grub-reboot works only on a cold reboot (shutdown and then manual boot), but not on a simple
shutdown -r. With these usual reboot commands, Ubuntu 16.04 occasionally shows a few
Clearing orphaned inode messages, and then immediately goes back into
Started new Kernel Device Manager (with the shutdown and startup messages often even interleaved). I never see the GRUB2 screen, and, more importantly, I never get booted into my alternate grub entry.
OTOH, if I shut down and then manually power-on the machine, I see that
grub-reboot has indeed marked the correct temporary option (not the one I've just left).
As the whole point of
grub-reboot, for me, is to switch OS remotely, this isn't a good option.
How can I reboot and see GRUB?