A/UX 3.1 and earlier versions do NOT support the Time Synchronization Protocol (TSP), which is a DARPA UPD protocol for clock synchronization services on computers in a local area network.
Fortunately, there was a new version of inetd which includes the TSP protocol (timed, timeserver) for A/UX. It is public domain shareware, and is available at jagubox.gsfc.nasa.gov (128.183.44.1) via anon-ftp.
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