CKA Challenges : Scheduling Priority 1. Find Pod with highest priority: Challenge: Find the Pod with the highest priority in Namespace management and delete it. Tip: Priority is an attribute in the Pod specification. k -n management get pod -oyaml Solution: k -n management describe pod | grep -i priority -B 10 k -n management delete…

Kubelet uses liveness probe to know when to restart a container. For instance, a liveness probe could notice a deadlock where an application is running, unable to make any progress. Restarting a container in such a state can help to make the application more available despite bugs. Many applications running…

Role-based access control(RBAC) is a way of regulating access to computer/network resources. RBAC authorization uses the rbac.autherization.k8s.io API group to drive authorization decisions. To enable RBAC, start the api-server with the --authorization-mode flag set to comma separated list that includes RBAC as below, kube-apiserver --authorization-mode=Example,RBAC--other-options --more-options RBAC Resources:

Network policies are used to control traffic flow at the IP address or port level. Network policies are application centric which allow how a pod is allowed to communicate with various network entities. The entities that a pod can communicate are identified through the combination of following, Other pods that…

Ingress is an API object that manages external access to services in the cluster. Ingress provides, Load balancing SSL termination Name-based virtual hosting Ingress exposes the HTTP and HTTPS routes from outside the cluster to the services inside the cluster. Traffic routing is controlled by the rules defined on the…

Kubeadm by default runs a single member etcd cluster in a static pod managed by control plane. This type of cluster can not sustain when any member become unavailable as there is only one member in the cluster. Hence having cluster with multiple members is good to handle the high…

Upgrade a primary control plane node. Upgrade additional control plane nodes. Upgrade worker nodes. Upgrade a primary control plane node Step 1: Upgrade kubeadm > apt-get update && apt-get install -y — allow-change-held-packages kubeadm=1.22.x-00 where x is the required version Check the download works and has the expected version using kubeadm version Verify the upgrade plan using kubeadm upgrade plan…

We can create a mock server in Postman and make requests that return the mocked data defined if no production API is ready or do not want to run the API requests against real data. We can simulate the behavior of real API by adding a mock server to the…