When working with remote computers or when there is no keyboard, it is sometime useful to be able to remotely (SSH, for example) order boot to another device.
Ordering boot to another operating system is easy on GRUB.
I have even found a method to order boot to PXE on GRUB.
Now I would like to do the same for USB devices (like pendrives).
/dev/sdais my hard disk.
/dev/sdbis a USB pendrive with, say, some Linux live distro like Ubuntu inside.
Can I order reboot to
If appropriate, adding an option (menu entry) to GRUB would be fine. If not, any other method could be worth too.
Command line methods are preferred.
Methods that do not require to phisically sit on the remote computer are preferred. This is: the useful part of using GRUB here is sending the order via remote methods.