Perhaps you’ve been charged with developing a container-based application infrastructure? If so, you most likely understand the value that containers can provide to your developers, architects, and operations team. In fact, you’ve likely been reading up on containers and are excited about exploring the technology in more detail. However, before diving head-first into a discussion about the architecture and deployment of containers in a production environment, there are three important things that developers, architects, and systems administrators, need to know
Continue reading “Architecting Containers Part 1: Why Understanding User Space vs. Kernel Space Matters”
The promise of Docker is that it simplifies application deployment, allows greater application density on hosts, and features a portable format that offers unparalleled flexibility over standard packaging. But one thing Docker doesn’t get you is the simplicity of `yum install foo` to install an application. Nor can Docker define or process a directed graph of container orchestration dependencies. We aim to change that.
Continue reading “Announcing “Yum + RPM for Containerized Applications” — Nulecule & Atomic App”
In a recent blog post on the appc spec, I mentioned Project Atomic’s evolving Nulecule [pronounced: noo-le-kyul] spec as an attempt to move beyond the current limitations of the container model. Let’s dig a bit deeper into that.
Continue reading “The Atomic App Concept…”It All Starts When a Nulecule Comes Out of its Nest””
At this week’s CoreOS Fest in San Francisco, CoreOS is – unsurprisingly – pushing hard on the Application Container Spec (appc) and its first implementation, rkt, making it the topic of the first session after the keynote and a bold story about broad adoption.
When making technology decisions, Red Hat continuously evaluates all available options with the goal of selecting the best technologies that are supported by upstream communities. This is why Red Hat is engaging upstream in appc to actively contribute to the specification.
Red Hat engages in many upstream communities. However, this engagement should not imply full support, or that we consider appc or rkt ready for
Continue reading “rkt, appc, and Docker: A Take on the Linux Container Upstream”
Linux containers have been getting a lot of hype recently, and it’s easy to understand why. Delivering applications to meet the demands of the business is challenging and containers are disrupting traditional application development and deployment models, enabling businesses to explore new, better ways to deliver products and services.
New innovations like the Docker image format and Kubernetes give you a simpler way to quickly create, package, assemble, and distribute applications. But with hype comes misunderstandings and misconceptions.
Join Red Hat and Cisco tomorrow, May 5, 2015 at 11:00 AM ET / 8:00 AM PT for the webcast, Top 6 Misconceptions about Linux Containers, to gain clarity around these misconceptions. In the webcast, you will:
- Gain a pragmatic look at Linux containers.
- Understand what benefits containers can deliver for you.
- Discover what security, implementation, and other considerations you should understand before your organization embraces this technology.
If you haven’t already done so, register today.
If you’re working with container images on Red Hat Enterprise Linux 7.1 or Red Hat Enterprise Linux Atomic Host, you might have noticed that the search and pull behavior of the included docker tool works slightly differently than it does if you’re working with that of the upstream project. This is intentional.
When we started the planning process for containers in RHEL 7.1, we had 3 goals in mind:
- Give control over the search path to the end-user administrator
- Enable a federated approach to search and discovery of docker-formatted container images
- Support the ability for Red Hat customers to consume container images and other content included as part of their Red Hat Subscription
The changes we implemented, which are documented on the Red Hat Customer Portal, affect three different areas of the tool:
Continue reading “Understanding the Changes to ‘docker search’ and ‘docker pull’ in Red Hat Enterprise Linux 7.1”
Earlier in March we announced the general availability of Red Hat Enterprise Linux 7 Atomic Host, a small footprint, container host based on Red Hat Enterprise Linux 7. It provides a stable host platform, optimized for running application containers, and brings a number of application software packaging and deployment benefits to customers. In my previous container blog I gave the top seven reasons to deploy Red Hat Enterprise Linux 7 Atomic Host. One reason was the ability to do atomic updates and rollbacks. In this blog I provide an in-depth look into atomic updating and how it differs from a yum update. And, speaking of atomic updates
Continue reading “Red Hat Enterprise Linux Atomic Host: Updates Made Easy”
As product manager for Red Hat Enterprise Linux 7, part of my job is to ensure that the latest version of our flagship product adheres to our promise of stability, reliability, and security. In addition, as Red Hat Enterprise Linux 7 is Red Hat’s latest enterprise Linux platform, it also needs to incorporate new innovations in technology to help our customers gain business advantage, reduce costs, and increase efficiency without compromising their existing investments. With this in mind, the Red Hat Enterprise Linux team takes great care in evaluating new technology to ensure that it is introduced in a manner that is minimally intrusive (if at all) and is a natural fit for the platform. Support for Linux containers and the ability to host container-based applications are great examples of this and Red Hat Enterprise Linux 7 stands ready for the challenge.
Creating and operating application containers via process isolation is not a new concept. Red Hat Enterprise Linux 6 sowed the seeds for this way back in 2010 with the introduction of Control Groups (cgroups). Since that time there have been many exciting developments in this area with active participation from Red Hat. Building upon cgroups functionality, enhancements to the kernel combined with an easy-to-use container format (Docker) make now an opportune time to consider deploying container-based applications on Red Hat Enterprise Linux 7.
Here are the top three reasons to consider Red Hat Enterprise Linux 7 as the host for your container-based applications
Continue reading “Top 3 Reasons to Run Container-Based Applications on Red Hat Enterprise Linux 7”
The OpenShift Online Technical Operations team was looking forward to the beta availability of Red Hat Enterprise Linux Atomic Host. In fact, they participated in early sprints as part of the Atomic Special Interest Group (SIG) to help make sure Red Hat Enterprise Linux Atomic Host had the operational “beef” to stand high alongside Red Hat’s other enterprise products. Part of this process led to us running the unreleased bits in OpenShift Online prior to the beta announcement.
That said, we’re not using it to run some corner niche of our infrastructure. Instead, we are using the Red Hat Enterprise Linux Atomic Host + Docker combo to run our reverse proxy tier. This means that every API, www.openshift.com, and web console request made to OpenShift Online runs through this tier.
So why all the interest? The small size of Red Hat Enterprise Linux Atomic Host is the
Continue reading “How Red Hat Enterprise Linux Atomic Host Powers OpenShift Online”
Applications don’t always work as expected, and “it works fine on my machine” — the first line of response when reporting an issue — has been around for decades. One way to avoid the challenge of application issues in production is to maintain identical environments for development, testing, and production. Another is to create a Continuous Integration environment, where code is compiled and deployed to test machines and vetted with each and every code check-in, long before being pushed to production.
Continue reading “Containers: Stumbling on the Road to Utopia”