TIME-3116 - Stratum 16 servers

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

Control details


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.

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Lynis is a technical security auditing tool for Unix flavors like Linux, macOS, AIX, Solaris, and *BSD. It is open source software and free to use. Typical usage include system hardening, compliance testing, and vulnerability scanning. The project has an active community, including development via GitHub.

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