Security Controls

TIME-3116 - Stratum 16 servers


Time servers are used to sync the time with the host. When a used server is not properly configured or not working, it will be listed as a stratum 16 server, giving it a very low priority. Usually when finding a server with a value of 16, the server should be checked or replaced with an alternative server.



How to solve

Any time server listed as a stratum 16 server is most likely not working correctly. This can be caused by the lack of connectivity, or too strict filtering. Check your NTP configuration to ensure all NTP servers are reachable and restart the NTP daemon.

Linux and Unix System Hardening

This information is provided as part of the Lynis community project. It is related to Lynis control TIME-3116. All information should be considered as-is, without guarantees. Any advice or snippets should be tested before implementing in production environments.


Lynis is a technical security audit tool for systems running Linux, UNIX, *BSD, and macOS. It is open source software and free to use. The project has an active community, and can also be found on GitHub.

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