Network Time Protocol (NTP) is a widely deployed but oft-misunderstood Internet standard for time synchronisation. This presentation will cover why you should (and probably already do) use NTP, how it works, and an overview of configuration, troubleshooting, and monitoring. The focus will be on practical implementation in enterprise, cloud, and personal environments rather than history, theoretical grounding, or environments requiring extreme precision.

Topics covered will include (time permitting):

• overview of the NTP algorithms, strata
• installation & configuration with ntp.conf
• how to use ntpq for troubleshooting
• overview of monitoring tools
• how to use and participate in the NTP pool & comments on scale
• common myths & misconceptions, and best practices for avoiding them
• my experiences in building a sub-US$100 stratum 1 server

For more on the history and theoretical background of NTP, see Julien Goodwin's LCA2011 talk, "A Brief History of Time Synchronisation". Overlap with Julien's talk will be kept to an absolute minimum, although I will dispute/update some of his data.

The practical examples & demo will use the NTP reference implementation on Ubuntu 16.04 LTS, but the skills learned will be applicable to all Linux distributions, and the principles will likely apply to other NTP implementations and operating systems as well. The content on which this talk will be based is appearing in a series of blog posts, starting here.