Both programs can be used to inspect the state variables defined in the specification and, in the case of xntpdc , additional ones of interest. In addition, the xntpdc program can be used to selectively enable and disable some functions of the daemon while the daemon is running. If not present, the daemon detaches from the controlling terminal and proceeds autonomously. If one or more -d switches are present, the daemon does not detach and generates special output useful for debugging. In general, interpretation of this output requires reference to the sources.
Some problems are immediately apparent when the daemon first starts running.
Note that NTP does not use TCP in any form. Other problems are apparent in the system log file. The log file should show the startup banner, some cryptic initialization data, and the computed precision value. The next most common problem is incorrect DNS names. Check that each DNS name used in the configuration file responds to the Unix ping command.