Specifies the protocol to be used on the filer to synchronize its time with another host or a timed server:
rfc868 (rdate) -- synchronizes the filer's time with the time on another host with an accuracy of one second.
ntp (SNTP for Simple Network Time Protocol) -- synchronizes the filer's time with the time on a time server to a theoretical maximum accuracy of one nanosecond; actual accuracy depends on the accuracy of the time server and network delays.