Troubleshooting SNTP

You have various options to solve problems that are related to Simple Network Time Protocol (SNTP). Here are some common problems that your system might encounter when you adjust time using SNTP.

The following list identifies problems you might encounter and provides a way to recover:

  • Contact an SNTP server through a firewall

    If you use the SNTP client through a firewall, you might need to configure the firewall to allow the User Datagram Protocol (UDP) packets to pass on port 123.

  • Server does not serve time to clients

    If you have selected Server must be synchronized before valid time is served on the Server page of SNTP properties, you must configure the system as an SNTP client that is connected to an active time server before the server can respond to client polls.

  • Stop SNTP

    If SNTP does not make correct time adjustments or if you want to start a new time adjustment, you must ensure that SNTP is stopped properly.

Logging SNTP activity can help you identify problems with the server or client.