z/OS Container Extensions (zCX) content solution

IBM® z/OS® Container Extensions (IBM zCX) makes it possible to integrate Linux on Z applications with z/OS. Application developers can develop and data centers can operate popular open source packages, Linux applications, IBM software, and third-party software together with z/OS applications and data.

IBM provides a Linux distribution configured to run Docker CE. IBM supplied support code will simplify installation and operation. Clients can participate with their own Linux applications that can easily be packaged in Docker format and deployed in the same way as open source, IBM, and vendor packages. Container Extensions runs on IBM z15™ and z14™ systems.

Learn about zCX performance benefits compared to x86

Big Picture: z/OS Container Extensions (zCX)

decide whether zcx is the right solution for you

1. Decide whether zCX is the right solution for you.

prepare your system and plan for you zcx instance

2. Prepare your system and plan for your zCX instance.

provision a zcx instance using the zosmf workflow

3. Provision a zCX instance using the z/OSMF workflow.

deploy your first docker container in your zcx instance

4. Deploy your first Linux container in your zCX instance.

manage and maintain your zcx instance

5. Manage and maintain your zCX instance.

How to get started with z/OS Container Extensions (zCX)

Frequently Asked Questions

Q: What are the benefits of z/OS Container Extensions?

A: z/OS Container Extensions expands and modernizes the z/OS software ecosystem to include Linux on Z applications. Most applications (including Systems Management components and development tools) that are currently only available to run on Linux will be able to run on z/OS as Docker containers. zCX runs Linux on Z applications on z/OS, using existing z/OS operations staff and reusing the existing z/OS environment. zCX maintains operational control within z/OS and z/OS Qualities of Service (scalability, availability, integrated disaster recovery, backup, WLM, and integration with z/OS security).

Q: Do application developers require knowledge of z/OS to create and deploy Linux on Z applications to run in z/OS Container Extensions?

A: Applications will look like Docker applications to the developer, not z/OS applications. If your application comes from Linux on Z, then no z/OS skills are required. Docker and Linux knowledge are all that is required.

Q: What are the costs associated with z/OS Container Extensions?

A: zCX is a base element of z/OS. There is no additional software cost for zCX itself beyond z/OS. Associated costs are hardware (z14, FC 0104, optionally zIIPs) and any software licensing of Linux on Z applications running inside zCX. IBM Container Hosting Foundation for z/OS delivers Monthly License Charge (MLC) pricing to satisfy the requirement for FC 0104. For more information, see Program Directory for IBM Container Hosting Foundation for z/OS.

Q: Can I install the APAR and enable the 90-day zCX trial in more than one LPAR or on more than one CPC?

A: You can use the 90-day zCX Trial no more than one time per sysplex. The sysplex can span multiple CPCs.

Q: Does Container Extensions make use of Kubernetes?

A: No, not at this time. The initial release of zCX for IBM z/OS V2.4 provides Docker Swarm as support for Docker cluster management. IBM’s future plans intend to include Kubernetes clustering for the orchestration, scalability, and management of zCX with compatible cloud platforms.

Q: How is Container Extensions different from Linux on Z?

A: zCX gives z/OS environments the ability to deploy Linux on Z applications as Docker containers for workloads with an affinity to z/OS. It is not a replacement for traditional Linux on Z environments.

If you are a client with Linux on Z installations, you will continue to run those installations. If you are a z/OS client that used to, but no longer has a Linux on Z installation, you should consider zCX. If you are a z/OS client that has never had a Linux on Z installation, then zCX Extensions is a low effort way to try Linux on Z.

Q: On which engine types can z/OS Container Extensions run?

A: z/OS Container Extensions address spaces are zIIP-eligible. Most zCX processing (including Docker containers deployed within zCX) can be dispatched on available zIIP processors. Some zCX processing will be dispatched on standard processors. This will generally be a much smaller percentage of processor cycles compared to what can execute on zIIPs. Running the Acme Air benchmark on zCX, up to 98% of the zCX CPU consumption was measured to be zIIP eligible.*

A good first assumption is that the new work running in the zCX environment will be 95% zIIP-eligible. However, your zCX environment may be more or less zIIP eligible depending on characteristics of the workload. Capacity planning should be based on the measured zIIP eligibility of your specific zCX applications. zCX can be deployed exclusively on standard processors if no zIIP processors are available. See "Exploiting zIIP and general purpose processors for zCX workloads" in the IBM z/OS Container Extensions Guide for more information.

* Results were extrapolated from internal IBM benchmarks performed in a controlled environment using a single z14 z/OS 2.4 LPAR with TCP/IP inbound workload queuing (IWQ) for inbound traffic and two zCX containers: one running Node.js and one running a MongoDB database. zIIP eligibility is based on the CPU consumption of the work running on the zCX address spaces and the associated work on the TCPIP and VTAM address spaces. Results may vary.

Q: What can run in z/OS Container Extensions?

A: Anything with s390x architecture (the IBM Z opcode set) in Docker hub can be run in zCX. The code is binary compatible between Linux on Z and Container Extensions.

In addition to open source packages, there will likely be IBM and third-party software available. It is intended that clients can participate with their own Linux applications, which can easily be packaged in Docker format and deployed in the same as open source, IBM, and vendor packages.

Q: Are licenses required for applications running inside z/OS Container Extensions?

A: Yes, any licenses that you would procure to run applications in a traditional Linux on Z environment will also be required to run those same applications inside zCX. Licenses are the same as those used for traditional Linux on Z applications. If you are using an application on both Linux on Z and zCX environments, ensure you have enough licensed capacity available to run the application on all the cores on which it will be active.

Q: Is Processor Value Unit (PVU) Licensing effective for IBM applications running inside z/OS Container Extensions?

A: Yes, whatever PVU licensing is in effect for IBM software in the traditional Linux on Z environment is also in effect for zCX. Both General Purpose and zIIP engines are counted as cores.

Q: Will subcapacity pricing for Linux on Z IBM SW (Passport Advantage products) be supported in zCX?

A: Yes, sub-capacity pricing is supported through the IBM License Metric Tool.

For more information on IBM License Metric Tool enablement on zCX, refer to: Using the IBM License Metric Tool for sub-capacity pricing.

Use of IBM License Metric Tool is now mandatory for sub-capacity pricing for the zCX environment. Manual reporting is no longer acceptable.

Q: What are some zCX use cases?

A: z/OS software ecosystem expansion: Latest microservices, non-SQL databases, analytics frameworks, ICP, application server environment, and emerging programming languages and environments.

Systems management: Centralization of UI portals for management products and databases
z/OS modernization: Open source application development utilities.

Q: Will there be performance data published for zCX?

A: There is currently no plan to publish performance data for the zCX environment because performance is heavily reliant on individual configuration, workload, and networking characteristics.

Q: Are there samples and resources that I can look at to get started?

A: Yes. Visit the Open Mainframe Project, Ambitus, for samples, build recipes, and other resources to promote collaboration and knowledge sharing of open source technologies to modernize and expand the IBM Z platform.

Learn more

Additional resources and documentation for z/OS Container Extensions will be available on this page as they are released. For now, learn about Containers, Docker, and z/OSMF using the links below.

Take our IBM z/OS Container Extensions survey to help us understand interest and potential use cases for zCX. The survey will help us understand your needs and curate content for you.

Technical resources for z/OS Container Extensions (zCX)

IBM Redbook

Example video

Running IBM Aspera on zCX

Running MQ Client Concentrator on zCX

Running IBM Service Management Unite on zCX

Running App Connect Enterprise on zCX

Systems Magazine Article

MQ for z/OS Performance Report

IBM IT Economics Consulting and Research

What's new

October 7, 2021

A link to information about enabling Container Hosting Foundation was added to the Planning for zCX tab in the How to get started section.

September 30, 2021

New z/OS Container Extensions overview video.

July 1, 2021

Transcript added for z/OS Container Extensions overview video.

June 18, 2021

A new IBM Z Hot Topics article, Getting Better Performance for Your zCX Containers, was added to the Tutorial & instruction tab of the Technical resources section.

The links for other IBM Z Hot Topics acrticles, on the About zCX and Tutorial & instruction tabs in the Technical resources section, were updated to find the articles on the new IBM Z Hot Topics website.

June 4, 2021

Updates for the new IBM Container Hosting Foundation for z/OS were made to the Planning for zCX tab of the How to get started section and the Frequently Asked Questions section.

The Big Picture has been modified for accessibility.

May 10, 2021

Added new resources to the About zCX tab of the Technical resources section.

February 19, 2021

Changes were made to the Technical resources section as a result of the digital transformation of IBM Systems magazine content.

November 30, 2020

Added new resources to the About zCX and Use cases tabs of the Technical resources section.

July 22, 2020

IBM Systems Lab Services was added to the About zXC tab of the Technical resources section.

June 16, 2020

z/OS Communications Server Performance Summary Report was added to the Tutorial & instruction tab of the Technical resources section.

Tutorial video of Docker image development in zCX was added to the Tutorial & instruction tab of the Technical resources section.

Third tab of Technical resources section was changed from Events to Use cases.

Example video of using JupyterHub and zCX was added to the Use cases tab of the Technical resources section.

April 30, 2020

IBM Z Hot Topics article on the 90-day zCX Trial was added to the Tutorial & instruction tab of the Technical resources section.