Kubernetes Certified Administrator (CKA) 2024

CKA topics Kubernetes in a nutshell Lab environment kubeadm init sample output Buliding kubernetes clusters Networking kubeadm kubectl Contexts Resources CKA topics Cluster Architecture, Installation & Configuration: How to set up and configure a Kubernetes cluster, including how to install and configure a Kubernetes cluster using kubeadm, how to upgrade your cluster version, how to backup and restore an etcd cluster, and how to configure a pod to use secrets Workloads & Scheduling: How to deploy a Kubernetes application, create daemonsets, scale the application, configure health checks, use multi-container pods, and use config maps and secrets in a pod. You’ll also need to know how to expose your application using services Services & Networking: How to expose applications within the cluster or outside the cluster, how to manage networking policies, and how to configure ingress controllers Storage: How to create and configure persistent volumes, how to create and configure persistent volume claims, and how to expand persistent volumes Troubleshooting: How to troubleshoot common issues in a Kubernetes environment, including how to diagnose and resolve issues with pods, nodes, and network traffic Kubernetes in a nutshell Control plane management components that mother-hen nodes and pods. Key components: ...

December 22, 2023 · 7 min

React environment variables in an nginx container

Your React app is ready to ship. Congratulations! Packaging for production is (and should) be different from your development configuration. In the case of Create React App the toolchain is rich, includes development productivity conveniences such as hot reloading, source maps and custom environment variables. This toolchain is mind blowingly productive as you develop the app, npm start and watch the magic unfold. At this point, its possible to put the React app one big (~1.7GB) happy container: ...

August 21, 2021 · 3 min

Kubernetes

The name Kubernetes originates from Greek, meaning helmsman or pilot. Terminology Essentials Help Bash kubectl completion Web UI dashboard Pods Creating a pod Option 1: Imperatively with the CLI Option 2: Declaratively with YAML Port forwarding Managing pods Pod Health Deployments and ReplicaSets ReplicaSet Deployment Deployments with kubectl Deployment Options Rolling updates Blue Green Canary Rollbacks StatefulSets Services Service Types Port forwarding take 2 Services YAML NodePort example ExternalName example Testing Service and Pod with curl Storage Volumes Volume Types Viewing a Pods volumes emptyDir volume example PeristentVolumes and PeristentVolumesClaims StorageClasses Managing configuration with ConfigMaps and Secrets Defining ConfigMaps Consuming ConfigMaps Secrets Secret best practices Storing Secrets Using Secrets Secrets as environment variables Secrets as files Troubleshooting Logs Configuration verification Shell into Pod container The API General kubectl Waaay cool Samples node.js app microk8s Shell improvements PersistentVolume storage location Resources Terminology k8s is two concepts; the control plane and nodes. ...

August 18, 2020 · 20 min

LXC (Lexy)

Born in 2008, LXC (pronouced lexy) is a userspace interface for the Linux kernel containment features, that enables the creation and management of application containers. LXC leverages a number of kernel features to contain processes: Kernel namespaces (ipc, uts, mount, pid, network and user) Apparmor and SELinux profiles Seccomp policies Chroots (using pivot_root) Kernel capabilities CGroups (control groups) LXC containers are often considered as something in between a chroot and a full blown VM. The goal of LXC is to create an environment as close as possible to a standard Linux installation, without the need for a separate kernel. ...

January 18, 2018 · 4 min