This series of blogs was written by a team of technical consultants from IBM Client Engineering EMEA.
Hello and welcome to this series !
About this series
This series of blogs is for z/OS system programmers. It aims to demystify the use of containers on IBM zSystems. The blogs go through the impact that containers have on your work, compare the different ways of working, present the value & benefits, and give you links to more resources.
The series comes in three parts:
There are a growing number of options for containers on IBM zSystems but what do they mean for you? How do they change what you have to do during the lifecycle of a mainframe-hosted application? This part summarizes why containers have become so significant and the IBM options. In part 2 [link], two z/OS system programmers discuss experiences on z/OS Container Extension (zCX) technology under z/OS.
When they hear “containers” or “micro-services” many people just think “public cloud” or “hyperscaler”. Maybe are you, as a z/OS system programmer, thinking the same way ?
I believe it is not a matter of having one choice and a single model of deployment. This is absolutely too risky in uncertain times. Regulation in Europe, such as DORA (Digital Operational Resilience Act) looks to improve cyber-security and operational resilience but even these regulators are not taking the direction of having one single production platform.
I think some key applications and assets are much more relevant, compliant, secured and efficient by running within existing data centers. This is particularly true when they are running on a powerful and robust environment, like IBM zSystems, that scales and innovates to match the new business requirements.
An open, hybrid multi-cloud architecture is more likely to happen and sounds to me like a better strategy. Why ?
I found, in many of my customers engagements with IBM zSystems and working on architectural design partnerships that the most compelling motivators (in order of importance) are:
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Cost savings
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Increased agility and time to value
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Simplicity and lowering skill barriers
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Strategic fit for hybrid integration
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Performance benefits
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DevOps efficiencies and maintainability
So, a collision between two worlds is happening: the world of containers and the world of mainframes.
Containerization is impacting the traditional applications hosted on mainframes. There are more and more patterns around IBM zSystems application modernization where containers are playing a key role.
The success of containers really started with Docker. Instead of having to provision an entire virtual machine with one of the following ways:
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A specific operating system (OS)
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A specific version of each required middleware supported on the OS
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A specific version of the application compatible with supported languages
Docker provided a simple way to create a Linux image which is self-contained and which can be executed on any hardware on which it had been generated.
Binaries and libraries are part of the image so there are no more dependencies to the underlying OS of the virtual machine.
This gave a powerful solution to developers across the globe to quickly develop applications and move their code from Development, test/QA, pre-production and production environments.
Quickly, developers adopted this technology and started to manage a growing number of containers. Docker also provided Docker swarm, an orchestration engine for containers, but another solution was preferred by the infrastructure teams: Kubernetes.
With developers using containers and infrastructure teams deploying kubernetes to host and manage the containers, a new approach emerged: DevOps! As a reminder, DevOps is an approach to lean and agile software delivery that promotes closer collaboration between lines of business, development and IT operations.
There are now several options for containers on IBM zSystems.
Figure 1 Options for containers on IBM zSystems
So how has this approach affected IBM zSystems and more specifically, how is it changing the way of working for z/OS system programmers.
You can find a lot of articles and material answering the “Usual questions” presented here, on figure 1, but feel free to reach out to us for a deep dive session about containers on IBM zSystems.
The purpose of this blog is to focus on the differences with what a z/OS system programmer has to perform during the lifecycle of an application: in a traditional way & in a containerized way.
Modern versus Old?! Traditional or containerized? What differences?
Let’s go now to our second blog to take an example and discover two personas discussing about containers running on the z/OS Container Extension (zCX) technology under z/OS.
Additional References: