What is a Parallel Sysplex?

IBM® Parallel Sysplex enables you to run multiple copies of a z/OS as a single image, so you can manage multiple systems and resources from a single point of control. In a Parallel Sysplex, operating systems can span multiple systems and share their applications and data. Images can be added or removed as needed, while applications continue to run.



The key features of Parallel Sysplex

  • Automatic Restart Manager recovers and restarts critical subsystems, either on the same system or on a different system.
  • Coupling Facility provides high-speed caching, list processing and locking.   
  • GDPS offers disaster recovery and high availability by using a cluster across two or more sites with data mirroring.
  • Generic Resource Management helps prevent a single point of failure and balances middleware workloads.  
  • Resource sharing enables physical resources such as files, tape drives, consoles and catalogs to be shared.
  • Server Time Protocol enables servers and coupling facilities to maintain common time synchronization.
  • Sysplex Failure Manager specifies a policy for failure detection intervals and recovery actions to be automatically initiated.
  • z/OS Workload Manager manages workloads via dynamic resource distribution to move workloads to systems with capacity.


Client success

Related technology

What is Server Time Protocol?

Server Time Protocol (STP) is required for Parallel Sysplex implementations that span more than one CEC. It is a server-wide facility that is implemented in the Licensed Internal Code (LIC). STP presents a single view of time to Processor Resource/Systems Manager (PR/SM) to maintain time synchronization for multiple servers and Coupling Facilities.



Use this guide for achieving near-continuous application availability.

Coupling Facility (CF) options

Explore Coupling Facility technology alternatives.

CFLEVEL considerations

Learn about CPC support for coupling facility code levels.

CF structure duplexing

See how CF Duplexing provides the ultimate in resiliency for Coupling Facility resources.

IBM Z connectivity handbook

See the options available for IBM Z within the datacenter and beyond.

Related products


Learn about this multi-site application availability solution for disaster recovery.

Maximize uptime

Reduce the impact of planned or unplanned downtime.


*99.99999% disclaimer: Internal data based on measurements and projections was used in calculating the expected value. IBM Z servers must be configured in a Parallel Sysplex using z/OS 2.3 or above; GDPS management of data and middleware recovery across Metro distance systems and storage, including GDPS Metro Multi-site Workload and GDPS Continuous Availability; and DS888X with IBM HyperSwap. Necessary resiliency technology must be enabled, such as System Managed CF Structure Duplexing, Sysplex failure management and Capacity Provisioning Manager. Other configurations may provide different availability characteristics.