What is containerization? Containerization is approach in which application, dependencies and its configuration are all packaged together as container image. So, if a application requires, unix environment, with Java8 installed, with Tomcat installed and application artefacts placed in certain directory, all this will be part of container image. Just as Read more…
What are the different deployment strategies available with Kubernetes deployment? Re-Create Rolling Updates What is Re-Create Strategy? In re-create strategy: All earlier PODs are destroyed first. Then new PODs are created with new version. Problem: There is a time when application is down and can’t receive any request. What is Read more…
What is a Rollout? When you do a deployment, it is also called as rollout of new version. Kubernetes provides rollout command to help you manage a deployment using subcommands like “kubectl rollout undo deployment/abc” You can check history of deployment, it’s status, rollback, pause or resume deployment using rollout Read more…
What is a deployment? The process of manually updating containerized applications can be time consuming and tedious. Upgrading a service to the next version requires starting the new version of the pod, stopping the old version of a pod, waiting and verifying that the new version has launched successfully, and Read more…
What is ReplicaSets? Like ReplicationController, ReplicaSet also helps to maintain number of Pods of specific types. It’s a new generation of ReplicationController and replaces it completely. (ReplicationControllers will eventually be deprecated) What is the main difference between ReplicaSet and ReplicationController? The key difference between the ReplicaSet and the ReplicationController is, Read more…
What is Replication Controller? With Replication Controller, you specify how many numbers of specific Pod you want to keep running. And rest it will ensure that only those many numbers of Pods will run. It constantly monitors the list of running pods and makes sure the actual number of pods Read more…
What is Pod? POD is the smallest Deployable Unit Containers are not directly deployed in Kubernetes on Worker node but deployed as Pod Single Pod can contain one or more Containers. Characteristics of containers deployed in one POD: Address to each other via localhost Share IP Address Share environment Share Read more…
What is kubectl? Kubectl is a command line interface for interacting and running commands on Kubernetes clusters. It is also called as Kube Control. Example Commands kubectl cluster-info kubectl get nodes How to create deployment? kubectl run my-nginx –image nginx How to get nodes using kubectl? $ kubectl get nodes Read more…
Can you tell me all components of Master and Worker nodes? Yes, here they are: What is etcd and it’s role in Kubernetes? etcd is: Distributed key-value store Used by Kubernetes to store all data used to manage the cluster: It stores configuration data used by nodes. It also stores Read more…
What are main components of K8s? Here is hierarchy of components: Cluster: Node: Cluster have set of Nodes Node can be of two type: Master Node Worker Node POD: Work Node run container instances in form of POD. What is a Node? A node is a machine – physical or Read more…