Containers

Rootless containers with Podman: The basics

Rootless containers with Podman: The basics

prsethi
By Prakhar Sethi

As a developer, you have probably heard a lot about containers. A container is a unit of software that provides a packaging mechanism that abstracts the code and all of its dependencies to make application builds fast and reliable. An easy way to experiment with containers is with the Pod Manager tool (Podman), which is a daemonless, open source, Linux-native tool that provides a command-line interface (CLI) similar to the docker container engine.

In this article, I will explain the benefits of using containers and Podman, introduce rootless containers and why they are important, and then show you how to use rootless containers with Podman with an example. Before we dive into the implementation, let’s review the basics.

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Troubleshooting user task errors in Red Hat Process Automation Manager and Red Hat JBoss BPM Suite

Troubleshooting user task errors in Red Hat Process Automation Manager and Red Hat JBoss BPM Suite

agiertli
By Anton Giertli

I’ve been around Red Hat JBoss BPM Suite (jBPM) and Red Hat Process Automation Manager (RHPAM) for many years. Over that time, I’ve learned a lot about the lesser-known aspects of this business process management engine.

If you are like most people, you might believe that user tasks are trivial, and learning about their details is unnecessary. Then, one day, you will find yourself troubleshooting an error like this one:

User '[User:'admin']' was unable to execution operation 'Start' on task id 287271 due to a no 'current status' match.

Receiving one too many similar error messages led me to learn everything that I know about user tasks, and I have decided to share my experience.

User tasks are a vital part of any business process management engine, jBPM included. Their behavior is defined by the OASIS Web Services—Human Task Specification, which has been fully adopted by Business Process Model and Notation (BPMN) 2.0—the standard for business processes diagrams. The spec defines two exceptionally important things that I will discuss in this article: The user task lifecycle and task access control. Without further ado, let’s jump right in.

Note: These troubleshooting tips are applicable to Red Hat JBoss BPM Suite 6.2 and above and Red Hat Process Automation Manager 7.

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Migrating from Fabric8 Maven Plugin to Eclipse JKube 1.0.0

Migrating from Fabric8 Maven Plugin to Eclipse JKube 1.0.0

rokumar
By Rohan Kumar

The recent release of Eclipse JKube 1.0.0 means that the Fabric8 Maven Plugin is no longer supported. If you are currently using the Fabric8 Maven Plugin, this article provides instructions for migrating to JKube instead. I will also explain the relationship between Eclipse JKube and the Fabric8 Maven Plugin (they’re the same thing) and introduce the highlights of the new Eclipse JKube 1.0.0 release. These migration instructions are for developers working on the Kubernetes and Red Hat OpenShift platforms.

Eclipse JKube is the Fabric8 Maven Plugin

Eclipse JKube and the Fabric8 Maven Plugin are one and the same. Eclipse JKube was first released in 2014 under the name of Fabric8 Maven Plugin. The development team changed the name when we pre-released Eclipse JKube 0.1.0 in December 2019. For more about the name change, see my recent introduction to Eclipse JKube. This article focuses on the migration path to JKube 1.0.0.

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How to switch Red Hat OpenShift Virtualization from hardware virtualization to software emulation

How to switch Red Hat OpenShift Virtualization from hardware virtualization to software emulation

bson
By Bryant Son

OpenShift Virtualization is a feature of Red Hat OpenShift Container Platform (OCP) and OpenShift Kubernetes Engine that allows you to run and manage virtual machine workloads alongside container workloads. Based on the open source project KubeVirt, the goal of OpenShift Virtualization is to help enterprises move from a VM-based infrastructure to a Kubernetes-and-container-based stack, one application at a time.

In my previous article, I showed you how to set up and enable OpenShift Virtualization running on Amazon Web Services Elastic Compute Cloud (AWS EC2). In that article, I noted that OpenShift Virtualization looks for hardware virtualization by default, which requires a bare-metal server instance. If you are running OpenShift on AWS EC2, as I do, then you have to enable software emulation over the default hardware virtualization. Otherwise, you need a bare-metal instance from the public cloud provider or a pure bare-metal solution.

In this article, I show you how to switch OpenShift Virtualization from its default of hardware virtualization to QEMU-based software emulation. You will then be able to start and operate a virtual machine through OpenShift Virtualization, even in a non-bare metal instance such as AWS EC2.

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Cloud-native Java applications made easy: Eclipse JKube 1.0.0 now available

Cloud-native Java applications made easy: Eclipse JKube 1.0.0 now available

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By Marc Nuri

After nine months of incubation with the Eclipse Foundation, Eclipse JKube 1.0.0 is finally here. This release marks the final deprecation of the great Fabric8 Maven Plugin (FMP) project. JKube is a complete replacement of FMP and includes all of the major features. Projects relying on FMP to create Apache Maven Java containers should migrate to Eclipse JKube to take full advantage of the new features, bug fixes, and upstream project maintenance described in this article.

JKube is a collection of plugins plus a standalone Java library that fit into your Maven project. If you have a Java project that needs to get deployed into Kubernetes or Red Hat OpenShift, this is the right tool for you. JKube takes care of everything related to the cluster deployment while you, as a developer, get to concentrate on implementing your application without worrying about where it needs to be deployed.

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How to install the CouchbaseDB Operator for Red Hat OpenShift on your laptop using Red Hat CodeReady Containers and Red Hat Marketplace

How to install the CouchbaseDB Operator for Red Hat OpenShift on your laptop using Red Hat CodeReady Containers and Red Hat Marketplace

donschenck
By Don Schenck

Red Hat Marketplace is an online store of sorts, where you can choose the software that you want to install and run on your Red Hat OpenShift cluster. The analogy is a phone app store, where you select an app, and it’s automagically installed on your phone. With Marketplace, you simply register your cluster(s), select the software that you want, and it is installed for you. It could not be easier.

In this article, I show you how to install Couchbase Server Enterprise Edition on an OpenShift cluster. In my case, the cluster is running on Fedora 32 using Red Hat CodeReady Containers (CRC). Couchbase Server Enterprise Edition is currently available as a free trial, and CRC is also available at zero cost. This setup offers a no-risk way to try containers, Kubernetes, OpenShift, and, in this case, Couchbase. This is definitely “developers playing around with the software”-level stuff.

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Migrate your Java apps to containers with Migration Toolkit for Applications 5.0

Migrate your Java apps to containers with Migration Toolkit for Applications 5.0

miguel
By Miguel Pérez Colino

As a developer, you have probably experimented with Kubernetes. It’s also possible that you are already running several Java applications on a Kubernetes platform, maybe Red Hat OpenShift. These initial containerized applications were greenfield projects, where you enjoyed the benefits of a platform providing templated deployments, easy rollbacks, resource availability, security by default, and a manageable way to publish your services.

Now, you might be thinking, “How can I enjoy all of these benefits in my existing Java applications?” Most Java applications in production today are running on virtual machines (VMs), likely on an application platform that is not container friendly. So, how can you migrate them from the current platform to containers on Kubernetes?

It isn’t an easy task, but this is a problem that we have been working hard on for years. Red Hat’s Migration Toolkit for Applications (MTA) 5.0 is the latest resulting iteration: An assembly of tools that you can use to analyze existing applications and discover what is required to modernize them. Read on to learn MTA 5.0’s features and migration paths.

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Enable OpenShift Virtualization on Red Hat OpenShift

Enable OpenShift Virtualization on Red Hat OpenShift

bson
By Bryant Son

Imagine an information technology (IT) world where everything is ideal: Every company has switched over to cloud-native applications, every application is containerized, everything is automated, and the IT people see that the world is good. Things are not so ideal in the real world, though, as we know. Applications remain tightly coupled with traditional virtual machine (VM) resources such as software libraries and hardware resources. The effort to migrate them from VMs to containers seems insurmountable, requiring years of dedicated spending and hours from developers and software architects.

The dilemma is that companies want all of their applications to eventually run on containers, but they also need to support applications running on VMs until that glorious shift happens. Given that application migration from VMs to containers will happen over the long haul, some companies are exploring a lift-and-shift approach. In theory, lift-and-shift would let us migrate tightly-coupled legacy applications to a container platform like Red Hat OpenShift. Rather than rewriting application code, developers would simply write interfaces (essentially, code with patterns) that are compatible with the existing structure.

Unfortunately, this scenario is unrealistic for legacy projects involving hundreds of application modules and packages. Therefore, it is logical to ask: What if there was a way to support existing applications running on virtual machines and new applications running on containers in one unified container-based platform?

Luckily, there is a way: Use a Kubernetes-based platform like OpenShift.

In this article, I introduce OpenShift Virtualization, a feature for Red Hat OpenShift Container Platform (OCP). OpenShift Virtualization allows you to run and manage virtual-machine workloads alongside container workloads.

Note: As of version 2.4 when CNV went GA, Container-Native Virtualization was renamed OpenShift Virtualization.

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Developing micro-microservices in C on Red Hat OpenShift

Developing micro-microservices in C on Red Hat OpenShift

kboone
By Kevin Boone

Java holds its dominating position in enterprise middleware for good reasons; however, describing anything in Java as “micro” requires a generous interpretation. It isn’t unusual to find Java-based microservices that need half a gigabyte of RAM to provide modest functionality at a modest load. The trend toward serverless architectures, where services are started and stopped according to demand, does little to improve the situation.

It has recently become possible to compile Java to a native executable using tools like GraalVM. This technique, coupled with an optimized Java runtime like Quarkus, tames Java’s resource consumption to some extent.

Nevertheless, we should not lose sight of programming languages that were designed from the start to compile to native code, with little to no runtime overhead. Languages like Rust and Go have become popular, and justifiably so. For optimal runtime resource usage and millisecond startup times, though, it remains hard to beat C.

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