Podman

Deliver your applications to edge and IoT devices in rootless containers

Deliver your applications to edge and IoT devices in rootless containers

Applications are often developed, tested, and delivered in containers, and Red Hat OpenShift is a great platform for that purpose. Sometimes, however, the target machine is much smaller than a Kubernetes cluster. It might be an embedded server, industry PC hardware, or a single server.
Image: Systemd + Podman + Ansible.

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Use vim in a production Red Hat OpenShift container in 6 easy steps

Use vim in a production Red Hat OpenShift container in 6 easy steps

Disclaimer: In most cases, we don’t recommend editing files in a container. However, in rare cases, you might need to reproduce and slightly modify a file in a production container, especially when debugging. (In this case, the vim method I’m using works on Fedora 32 on my laptop and it is the base of my Red Hat OpenShift container image.)

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Operator integration testing for Operator Lifecycle Manager

Operator integration testing for Operator Lifecycle Manager

Operators are one of the ways to package, deploy, and manage application distribution on Red Hat OpenShift. After a developer creates an Operator, the next step is to get the Operator published on OperatorHub.io. Doing this allows users to install and deploy the Operator in their OpenShift clusters. The Operator is installed, updated, and the management lifecycle is handled by the Operator Lifecycle Manager (OLM).

In this article, we explore the steps required to test the Operator’s OLM integration. For demonstration, we use a simple Operator that prints a test message to the shell. The Operator is packaged in the recently introduced Bundle Format.

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Getting started with Buildah

Getting started with Buildah

If you’re looking to build Open Container Initiative (OCI) container images without a full container runtime or daemon installed, Buildah is the perfect solution. Now, Buildah is an open source, Linux-based tool that can build Docker- and Kubernetes-compatible images, and is easy to incorporate into scripts and build pipelines. In addition, Buildah has overlap functionality with Podman, Skopeo, and CRI-O.

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Transitioning from Docker to Podman

Transitioning from Docker to Podman

Podman is an excellent alternative to Docker containers when you need increased security, unique identifier (UID) separation using namespaces, and integration with systemd. In this article, I use real-world examples to show you how to install Podman, use its basic commands, and transition from the Docker command-line interface (CLI) to Podman. You’ll also see how to run an existing image with Podman and how to set up port forwarding.

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Red Hat Enterprise Linux 8.3 supports faster service and workload delivery

Red Hat Enterprise Linux 8.3 supports faster service and workload delivery

Red Hat Enterprise Linux (RHEL) 8.3 was announced last week and is now generally available. We encourage Linux developers to download this update and give it a try. We also recommend updating both development and production systems to the new 8.3 release. This article is an overview of the developer highlights of RHEL 8.3, including new application streams for Node.js 14, Ruby 2.7, PHP 7.4, GCC Toolset 10, and more.

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Rootless containers with Podman: The basics

Rootless containers with Podman: The basics

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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Introducing the Red Hat build of the OpenJDK Universal Base Images—now in Red Hat Enterprise Linux 8.2

Introducing the Red Hat build of the OpenJDK Universal Base Images—now in Red Hat Enterprise Linux 8.2

With the recent release of Red Hat Enterprise Linux 8.2, we also added the first Red Hat build of OpenJDK Universal Base Images. These General Availability (GA) images for OpenJDK 8 and OpenJDK 11 set a new baseline for anyone who wants to develop Java applications that run inside containers in a secure, stable, and tested manner.

In this article, we introduce the new OpenJDK Universal Base Images and explain their benefits for Java developers. Before we do that, let’s quickly review what we know about UBIs in general.

About Universal Base Images

Red Hat Universal Base Images (UBIs) are:

OCI-compliant container base operating system images with complementary runtime languages and packages that are freely redistributable. Like previous base images, they are built from portions of Red Hat Enterprise Linux (RHEL). UBI images can be obtained from the Red Hat container catalog and be built and deployed anywhere.

In other words, UBIs help application developers reach the secure, stable, and portable world of containers. These images are accessible using well-known tools like Podman/Buildah and Docker. Red Hat Universal Base Images also allow users to build and distribute their own applications on top of enterprise-quality bits that are supportable on Red Hat OpenShift and Red Hat Enterprise Linux.

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How to customize Fedora CoreOS for dedicated workloads with OSTree

How to customize Fedora CoreOS for dedicated workloads with OSTree

In part one of this series, I introduced Fedora CoreOS (and Red Hat CoreOS) and explained why its immutable and atomic nature is important for running containers. I then walked you through getting Fedora CoreOS, creating an Ignition file, booting Fedora CoreOS, logging in, and running a test container. In this article, I will walk you through customizing Fedora CoreOS and making use of its immutable and atomic nature.

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