Managing Kubernetes

CLI

• kubectl (Kube control) Kubernetes Command Line Interface (CLI) client to manage cluster resources and applications.

• It is very flexible and easy to integrate with other systems, therefore it can be used standalone, or part of scripts and automation tools.

• Once all required credentials and cluster access points have been configured for kubectl, it can be used remotely from anywhere to access a cluster.

• Recommended to be separately installed, kubectl receives its configuration automatically for Minikube Kubernetes cluster access.

  • However, in different Kubernetes cluster setups, we may need to manually configure the cluster access points and certificates required by kubectl to securely access the cluster.

Dashboard

Kubernetes Dashboard

• a Web-based User Interface (Web UI) to interact with a Kubernetes cluster to manage resources and containerized applications.

• While not as flexible as the kubectl CLI client tool, it is still a preferred tool to users who are not as proficient with the CLI.

Minikube & Dashboard

• Minikube installs the Dashboard as an addon, but it is disabled by default.

• Prior to using the Dashboard we are required to enable the Dashboard addon, together with the metrics-server addon, a helper addon designed to collect usage metrics from the Kubernetes cluster.

• To access the dashboard from Minikube, we can use the minikube dashboard command, which opens a new tab in our web browser displaying the Kubernetes Dashboard, but only after we list, enable required addons, and verify their state.

    minikube addons list

    minikube addons enable metrics-server

    minikube addons enable dashboard

    minikube addons list

    minikube dashboard

    minikube dashboard --url # Request url of dashboard

API Directory Tree

HTTP API Tree

• The tree can be divided into three independent group types.

  • Core group (/api/v1)

    • This group includes objects such as Pods, Services, Nodes, Namespaces, ConfigMaps, Secrets, etc.

  • Named group

    • This group includes objects in /apis/$NAME/$VERSION format. These different API versions imply different levels of stability and support:

    • Alpha level - it may be dropped at any point in time, without notice. For example, /apis/batch/v2alpha1.

    • Beta level - it is well-tested, but the semantics of objects may change in incompatible ways in a subsequent beta or stable release. For example, /apis/certificates.k8s.io/v1beta1.

    • Stable level - appears in released software for many subsequent versions. For example, /apis/networking.k8s.io/v1.

  • System-wide

    • This group consists of system-wide API endpoints, like /healthz, /logs, /metrics, /ui, etc.

• We can access an API Server either directly by calling the respective API endpoints, using the CLI tools, or the Dashboard UI.