The IBM Z time synchronization solution uses two technologies to ensure precise, consistent, and resilient timekeeping across IBM Z systems; Server Time Protocol (STP) and External Time Sources (ETS). STP is a server-wide facility that is implemented in the Licensed Internal Code (LIC) of the IBM Z® platform. It provides improved time synchronization in a sysplex or non-sysplex configuration. ETS on IBM Z supports standard protocols like Network Time Protocol (NTP), Precision Time Protocol (PTP), and Pulse Per Second (PPS) to keep accurate universal time.

This IBM Redbooks® publication is intended for infrastructure architects and system programmers who need to understand the STP and ETS functions. Readers are expected to be familiar with IBM Z technology and terminology.

This book provides planning and implementation information for STP and ETS functions and associated software support for the IBM z17™, IBM z16®, and IBM z15® platforms.

Chapter 1. The critical role of time synchronization in IT systems

Chapter 2. Accurate timekeeping with IBM Z

Chapter 3. CTN configuration and operations

Chapter 4. External Time Source configuration and management

Chapter 5. Advanced CTN configurations and time management operations