For ages I've been getting annoyed at Xen for having to set the Independant_WallClock setting back to 1 after every reboot, so that NTP will work. I even added this stuff into the config; http://os-drive.com/files/docbook/xen-faq.html#virtual_guest_clock And despite thatm it still got reset to 0 after a reboot. Today I found the answer. Today I found this in my config file: # Set independant wall clock time xen.independant_wallclock = 1 10 points for anyone who spots as I did the immense FAIL...