Managing multiple Kubernetes clusters is a pain. From switching between multiple clusters and managing applications and microservices deployed in multiple namespaces. Here are some commands and tools I use every day to help manage multiple Kubernetes clusters.

Aliasing

Some basic aliasing can help speed up the process of deploying and managing Kubernetes clusters. Here is some aliasing that I use almost every day.

Aliasing just the simple kubectl can save lots of time since we type them in front of every k8s command.

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alias k=kubectl

A namespace is useful in separating different components and applications in a Kubernetes cluster, but it can be a pain to specify the namespace every time.

For example, if we want to get the pods in the istio-system namespace

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kubectl get pod --namespace istio-system

Permanently saving the namespace for all subsequent kubectl commands in the context can reduce lots of time and typos.

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alias kns='kubectl config set-context --current --namespace'

In the example, when we run kns default we switched to the default namespace for all of the subsequent kubectl commands for that cluster.

Using --dry-run=client and outputting it as yaml file can quickly generate the yaml for a Kubernetes resource without actually applying it.

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alias kdr='kubectl --dry-run=client -o yaml'

kubecm

kubecm is great for visualizing and managing multiple Kubernetes clusters in your kubeconfig file.

To install simply run

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brew install kubecm

alias kc='kubecm'

You can list all your Kubernetes clusters as a table along with the server and the current namespace by using kc list or kc l.

Also, you can interactively select clusters and namespaces to switch between them by typing kc ns. Searching is also possible in case you have lots of clusters and namespace to manage.

Apart from this, kubecm can also be used to create, delete and merge multiple kubeconfig files.

kube-ps1

kube-ps1 is a shell script that simply adds Kubernetes Cluster and Namespace information to the prompt. It is very useful for quickly viewing your current cluster and namespace to make sure you deployed stuff in the right place.

To install simply run

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brew install kube-ps1

source "/opt/homebrew/opt/kube-ps1/share/kube-ps1.sh"
PS1='$(kube_ps1)'$PS1

In the example below, initially, we are in the jenkins namespace in the minikube cluster. Then we switch to the default namespace we can see that the shell prompt is updated accordingly.

kubectl-tree

kubectl-tree is a tool to observe the hierarchy and status of Kubernetes objects in a tree format. It is useful for visualizing the hierarchy of objects in a namespace and debugging Kubernetes objects. This tool comes in handy when you are trying to manage complex object hierarchies such as in knative.

To install simply run

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kubectl krew install tree

We can see the object tree that which deployments are managing which replicasets and pods.