Need

Accurate timestamping for traceability

Context

• Usage of Elixir (v1.11+) for building scalable and fault-tolerant applications
• Usage of Logger module for logging

Description

Non compliant code

        def log_event(event) do
  Logger.info("{#{DateTime.utc_now()}} - #{event}")
end
        
        

This function logs an event with a timestamp that is based on the system's internal clock, which may not be synchronized with an NTP server. If the internal clock is wrong, the logged timestamps will also be wrong, causing a loss of traceability.

Steps

• Make sure your server's clock is synchronized with an NTP server.
• Ensure the application relies on this synchronized time for timestamping logs.

Compliant code

        def log_event(event) do
  Logger.info("{#{DateTime.utc_now()}} - #{event}")
end
        
        

In the corrected code, the function's behavior doesn't change because the NTP synchronization happens at the system level. The function still uses DateTime.utc_now(), but now the underlying system time is correctly synchronized with an NTP server. This ensures accurate timestamps in logs.

References

• 064. Traceability loss - Server's clock