Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand. Do you want…
Question 1 – Add containers to a Kubernetes pod on runtime or Allow containers to be added to a running pod Answer: Adding or removing containers to a pod is not possible, since the container list in the pod spec is immutable. However, you can create a POD with multiple Containers at Instantiation of pod….
RHEL / Centos Ubuntu How to remove or cleanup kubernetes worker nodes in Centos 7? How to remove or cleanup kubernetes worker nodes in Ubuntu? Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market…
What is Kubeadm? Kubeadm helps you bootstrap a minimum viable Kubernetes cluster that conforms to best practices. Kubeadm is a tool built to provide kubeadm init and kubeadm join as best-practice “fast paths” for creating Kubernetes clusters. Goal To Install a single master Kubernetes cluster To Install a high availability master Kubernetes cluster To Install…
What is Kubeadm? Kubeadm helps you bootstrap a minimum viable Kubernetes cluster that conforms to best practices. Kubeadm is a tool built to provide kubeadm init and kubeadm join as best-practice “fast paths” for creating Kubernetes clusters. Goal To Install a single master Kubernetes cluster To Install a high availability master Kubernetes cluster To Install…
Errors Solutions https://stackoverflow.com/questions/39872332/how-to-fix-weave-net-crashloopbackoff-for-the-second-node Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand….
Errors Solutions https://stackoverflow.com/questions/47107117/how-to-debug-when-kubernetes-nodes-are-in-not-ready-state https://stackoverflow.com/questions/50085323/kubernetes-worker-node-staying-in-notready-state Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at…
Error 1 Error 1 Error 2 Error 3 Solutions 3 Error 4 Solutions 4 Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic…
With the release of Kubernetes v1.14, Windows Server node support has officially graduated from beta to stable! This support enables developers and operators with Windows Server based applications to containerize them and benefit from the power of Kubernetes. Prior to this support, The v1.5 release of Kubernetes introduced alpha support for Windows Server based workers…
The hostPath volume mounts a resource from the host node filesystem. the resources could be directory, file socket, character, or block device. These resources mu A hostPath volume mounts a file or directory from the host node’s filesystem into your pod. A hostPath PersistentVolume must be used only in a single-node cluster. Kubernetes does not…
Here are the following facts for emptyDir storage type in Kubernetes An emptyDir volume is first created when a Pod is assigned to a Node and initially its empty A Volume of type emptyDir that lasts for the life of the Pod, even if the Container terminates and restarts. If a container in a Pod…
Kubernetes supports multiple virtual clusters backed by the same physical cluster. These virtual clusters are called namespaces. Namespaces ca be used in multiple environment with many users spread across multiple teams, or projects. Names of resources need to be unique within a namespace, but not across namespaces. Namespaces are a way to divide cluster resources…
A Probe is a diagnostic performed periodically by the kubelet on a Container. To perform a diagnostic, the kubelet calls a Handler implemented by the Container. There are three types of handlers: Each probe has one of three results: The kubelet can perform and react to two kinds of probes on running Containers: In this…
A Probe is a diagnostic performed periodically by the kubelet on a Container. To perform a diagnostic, the kubelet calls a Handler implemented by the Container. There are three types of handlers: Each probe has one of three results: The kubelet can perform and react to two kinds of probes on running Containers: In this…
The CoreOS corporation was acquired by Red Hat in May 2018 for $250 million; post-acquisition, the main enterprise Container Linux distribution, combined with Red Hat’s similar Project Atomic, has been renamed Red Hat CoreOS, while its open source community has been aligned with the Fedora Project as Fedora CoreOS. Today, both teams(CoreOS & redhat) are…
Certified Kubernetes Administrator CKA Exam Curriculum Reference https://www.cncf.io/certification/cka/ https://github.com/certifications-tutorials/kubernetes-curriculum Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow…
CPU Based Scaling With Horizontal Pod Autoscaling, Kubernetes automatically scales the number of pods in a replication controller, deployment or replica set based on observed CPU utilisation. [code]$ kubectl get deployment $ kubectl autoscale deployment <deployment-name> –min=2 –max=5 –cpu-percent=80 $ kubectl get hpa[/code] So, now we have a hpa running for our deployment “tomcat02”. It…
Here are some of the known best alternative of Kubernetes which incudes. Docker Swarm A swarm is a group of machines that are running Docker and joined into a cluster. After that has happened, you continue to run the Docker commands you’re used to, but now they are executed on a cluster by a swarm…
Since v1.6.0, Kubernetes has enabled the use of CRI, Container Runtime Interface, by default. The container runtime used by default is Docker, which is enabled through the built-in dockershim CRI implementation inside of the kubelet. Other CRI-based runtimes which can be Alternative of Docker in Kubernetes include: containerd (CRI plugin built into containerd) – cri…
How to setup Kubernetes Dashboard in EKS using NodePort? Step 1: Deploy the Dashboard# Deploy the Kubernetes dashboard to your cluster: [code]kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml[/code] # Deploy heapster to enable container cluster monitoring and performance analysis on your cluster: [code]$ kubectl apply -f https://raw.githubusercontent.com/kubernetes/heapster/master/deploy/kube-config/influxdb/heapster.yaml[/code] # Deploy the influxdb backend for heapster to your cluster: [code]$…
What is Annotations in Kubernetes? There are two way using you can attach metadata to Kubernetes objects. labels annotations Kubernetes annotations is used to attach arbitrary non-identifying metadata to objects. Clients such as tools and libraries can retrieve this metadata. In contrast, annotations are not used to identify and select objects. The metadata in an…
In simple line, Amazon EKS is generally available, bringing fully-managed Kubernetes to AWS. Amazon launched Amazon EKS in November at its re:Invent 2017 conference. Till the time this article is written, Amazon EKS is available in the US East (N. Virginia) and US West (Oregon) Regions only. The cost of running EKS is $0.20 per…
Error 1 – Error starting host: Error getting state for host: machine does not exist [plain] <p style=”font-weight: 400;”>D:\kubernete>minikube-windows-amd64.exe start –kubernetes-version=”v1.8.0″ –vm</p> <p style=”font-weight: 400;”>-driver=”virtualbox” –alsologtostderr</p> <p style=”font-weight: 400;”>W0110 <span data-term=”goog_1571914274″>12:16:04.517163</span> 10504 root.go:148] Error reading config file at C:\Users</p> <p style=”font-weight: 400;”>\panan4\.minikube\config\config.json: open C:\Users\panan4\.minikube\config\conf</p> <p style=”font-weight: 400;”>ig.json: The system cannot find the file specified.</p> <p style=”font-weight: 400;”>I0110 <span…
Introduction “DevOps” is an emerging model that allows effective collaboration of development and Operations team so that they can build, test, and release software faster and more reliably. Traditionally in an organization, where a waterfall method is followed in which the development team tests the new code in an isolated development environment for quality assurance….