Hi; I'm having trouble with my unRAID server install on an ASRock - AD2550R/U3S3 MB. unRAID is a 3.15.0 kernel under Slackware, booted on a USB flash stick.

The issue is that the safe reboot (powerdown -r) script shuts down the server, but when it tries to reboot the boot hangs early in the process with the text "SYSLINUX 3..." on the screen. The same thing happens with the reboot command. I've tried different USB ports and different flash drives with different installs.

The reason I think this could be a BIOS/MB issue is because the same thing happens with a powerbutton shutdown. If I shut down by holding the PB for 3 seconds, then IMMEDIATELY push again to restart, it will hang. If I wait after shut down for as little as 3 seconds the reboot is usually fine.

I've looked for a BIOS setting to pause before a reboot, and I've seen reference to a setting called (something like "USB Bulk Media Delay") that appears to hold off on loading USB devices for 10 seconds or so. I don't see that in my BIOS.

TL/DR: Is there a way to add a several second delay to the re-boot sequence so that power-on happens say 5 seconds after power down?