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A faster startup and smaller memory footprint always matter in Kubernetes due to the expense of running thousands of application pods and the cost savings of doing it with fewer worker nodes and other resources. Memory is more important than throughput on containerized microservices on Kubernetes because:

Kubernetes, the de facto standard for container orchestration, has quickly grown to dominate the container environment both in terms of infrastructure management and application development. As an open source platform with a huge community of enthusiasts and professionals, and being a part of the Cloud Native Computing Foundation, Kubernetes has become not only a powerful and impressive orchestration system itself but it has fostered a huge ecosystem of related tools and services to make it easier to use and extend its functionality with ever more powerful and sophisticated components.

Have you wanted to cause chaos to test your systems but prefer to use visual tools rather than the terminal? Well, this article is for you, my friend.

Preparing to run a new (or convert an existing) application in Kubernetes takes work. Working with Kubernetes requires defining and creating multiple "manifests" for the different types of objects in your application. Even a simple microservice is likely to have a deployment.yaml, service.yaml, configmap.yaml, and other files. These declarative YAML files for Kubernetes are usually known as "manifests." You might also have to set up secrets, ingresses, persistent volumes, and other supporting pieces.

If you've tried FreeDOS, you might have been stymied by the command line. The DOS commands are slightly different from how you might use the Linux command line, so getting around on the command line requires learning a few new commands.

But it doesn't have to be an "all new" experience for Linux users. We've always included some standard Unix commands in FreeDOS, in addition to the DOS commands that are already similar to Linux. So if you're already familiar with the Linux command line, try these commands to help ease into FreeDOS:

Do you know how your system will respond to an arbitrary failure? Will your application fail? Will anything survive after a loss? If you're not sure, it's time to see if your system passes the Litmus test, a detailed way to cause chaos at random with many experiments.

The secure shell protocol (SSH) is the most common method for controlling remote machines over the command line in the Linux world. SSH is a true Linux original, and it is also gaining popularity in the Windows world. There is even official Windows documentation for SSH, which covers controlling Windows machines using OpenSSH.

FreeDOS is an open source DOS-compatible operating system that you can use to play classic DOS games, run legacy business software, or develop embedded systems. Any program that works on MS-DOS should also run on FreeDOS.

But if you've never used DOS, you might be confused about how to navigate the system. FreeDOS is primarily a command-line interface; there is no default graphical user interface (GUI) in FreeDOS. You need to type every command at the command line.

The Open Organization community celebrates its sixth anniversary on June 02. That's six years of articles (hundreds), books (an evolving series), conversations (always inspiring), teaching (we love it), and learning.

In my introductory article about chaos engineering, one of the main things I covered was the importance of getting the steady state of your working Kubernetes cluster. Before you can start causing chaos, you need to know what the cluster looks like in a steady state.

Throughout the 1980s and into the 1990s, I was primarily a DOS user. I loved the command line environment offered in DOS, which became more powerful with each successive release. I even learned how to write my own DOS programs in the C programming language so I could extend the DOS command line, and write more powerful replacements for the standard DOS commands. I'd experimented with Microsoft's Windows—but if you remember Windows 3 from that time, you know it was slow and tended to crash. But I preferred the command line anyway, so I stuck to DOS.

The serverless Java journey started out with functions—small snippets of code running on demand. This phase didn't last long. Although functions based on virtual machine architecture in the 1.0 phase made this paradigm very popular, as the graphic below shows, there were limits around execution time, protocols, and poor local-development experience.

Kubernetes is turning 11, so I'll be celebrating its birthday by giving you some open source tools that will help you cause chaos. Chaos engineering is part science, part planning, and part experiments. It's the discipline of experimenting on a system to build confidence in the system's capability to withstand turbulent conditions in production.

Before I start passing out the gifts, in this introductory article, I will explain the basics of how chaos engineering works.

Imagine the chaos that would occur if all open source software vanished with the snap of a finger. Picture the devices that would turn to bricks in our hands, the infrastructure that would fail, and the machinery that would fall silent.

The truth is we probably don't stop to think about all the open source libraries, frameworks, and components we depend on—until something goes wrong.

Breakfast …. It's the most important meal of the day, or so they say. But who wants to spend time on a big meal when you could be sleeping instead? (And if your breakfast is too big, you might feel the need to go back to sleep.)

Still, busy developers, sysadmins, and other IT pros need some fuel to start their day. So, we asked some of our contributors to tell us how they feed their hunger without "eating" into their rest or work time. Here's what they had to say.

My first attempt at Linux was one of those "maybe I should give this a try" kinds of situations.

Part of publishing services on the cloud is providing users and developers easy access to those services through easy and reliable means. One of the most popular methods of interfacing with applications online is through an application programming interface (API), a fancy term that means you allow users to interact with your app through code.

This isn't the first article I've written about trusted computing bases (TCBs), so if the concept is new to you, I suggest you have a look at What's a trusted compute base? to get an idea of what I'll be talking about here.

While working on a continuous integration/continuous development (CI/CD) solution for a customer, one of my first tasks was to automate the bootstrapping of a CI/CD Jenkins server in OpenShift. Following DevOps best practices, I quickly created a configuration file that drove a script to complete the job. That quickly became two configuration files when I realized I needed a separate Jenkins server for production.

More than 20 years ago, when Robert Maynord started teaching at Immaculate Heart of Mary School in Monona, Wisconsin, the school had only eight functioning computers, all running Windows 95. Through his expertise in and enthusiasm for Linux and open source software, Robert has transformed the school community, its faculty, and its students, who are in kindergarten to eighth grade.