““Implementing NTP Clients, Servers, and Client/Server Mode With NTP, servers supply information about the time of day to clients, and clients react by adjusting their clocks to match. The process requires repeated small adjustments over time to maintain that synchronization. The configuration itself can be simple (to the extent covered in this book), or it can be extensive once you add security configuration and redundancy. As an example, just to show the basic syntax and show commands, consider Figure 33-5. It has three routers, all of which will use NTP. R1 will act as an NTP client, R3 as an NTP server, but R2 will be in client/server mode.””
