I am getting a new microSD flash ready for deploying a large number of BeagleBones, Blacks and Greens. There's a new-ish u-boot feature that is required for this, but I can't know in advance what version of u-boot is present on the eMMC of these 'Bones. So, I have a small service that runs "After=local-fs.target syslog.target" which checks the boot loader, and upgrades it if needed. Now, I want to cause an immediate (ish) reboot. My attempts to use /sbin/reboot and /sbin/shutdown (and variants on nohup /sbin/shutdown) from this service have not succeeded. Is there a way to do this?