kubernetes-tools.md

Kubernetes - Tools, Tips & Tricks

k9s

k9s: Kubernetes CLI To Manage Your Clusters In Style!

Usage

When first opened, k9s show the list of pods.

From the Pods view, you can:

• Change the selected pod (Up, Down),

  • then doing actions with that selected pod (by pressing the key bindings in blue color), e.g.
    • Describe that pod, by pressing d
    • Logs, show logs of all containers of that pod, by pressing l
    • ...
    • View that selected pod, by pressing Enter

• Change the namespace (by pressing the key bindings in pink color)

  • to all by pressing 0
  • to default by pressing 1 (by default, k9s use default namespace)

• Change to another list (resource)

  • List all the resources, by pressing Ctrl +A
  • Change to the view for that resource, by pressing Enter

  for example: change back to the default view - Pods

  • Ctrl + A
    • Downs to select pods (the 2nd one)
    • Enter
  • Press : to enter command mode
    • Type in the command for pod: pod (or any of po,pod,pods,v1/pods - showed in Ctrl + A)

Action	Key Binding	Command	Note
Change the selected resource	Up - Down
View (the selected resource)	Enter		Available for any selected resource
Back	Esc
Quit K9s	Ctrl + C
Help	?		Available at any view, change depend on which view is showing
Show all available resource alias	Ctrl + A		1. Up/Down; 2. Enter (to close the Aliases view: use Ese or press Ctrl + A again)

Headlamp

Headlamp¹ (a CNCF Sandbox project²): A Kubernetes web UI that is fully-featured, user-friendly and extensible

Tips & Tricks

Use the right version of kubectl for each cluster/project with asdf

You must use a kubectl version that is compatible with your cluster control plane (kube-apiserver).

Why

kubectl is supported within one minor version (older or newer) of kube-apiserver.

e.g.

• kube-apiserver is at 1.30
• kubectl is supported at 1.31, 1.30, and 1.29

For more information, see

• Version Skew Policy
• kubectl
• Special Interest Group (SIG) Release's Repository Notes

How?

See the demo at asdf-demo repository

Make aliases for kubectl

• Just a simple alias k for kubectl

  • For zsh

    alias k="kubectl"

• Use shell plugin that provides a lot of aliases, e.g.

  • oh-my-zsh's plugin kubectl Some useful aliases the plugin adds: k, kaf, kga. For the full lists, see kubectl.plugin.zsh | ohmyzsh.

  • If you want more, kubectl-aliases add 800 aliases, see the full lists and the syntax explanation

Show cluster information in shell prompt

• oh-my-zsh plugin kubectx

• Use starship prompt, with its command for Kubernetes

• Use fish shell, which show it by default

Add shell completions for kubectl

Configuration for completion

• kubectl autocomplete | kubectl Quick Reference

• kubectl completion | kubectl Commands

  • for macOS: https://kubernetes.io/docs/tasks/tools/install-kubectl-macos/#enable-shell-autocompletion

  • for linux: https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/#enable-shell-autocompletion

  • for windows: https://kubernetes.io/docs/tasks/tools/install-kubectl-windows/#enable-shell-autocompletion

Add color to kubectl output with kubecolor

kubecolor colorizes your kubectl command output and does nothing else.

You can use kubecolor as a complete alternative of kubect

Configuration

• zsh

  # .zshrc
  alias k="kubectl"
  
  if [ "$(command -v kubecolor)" ]; then
    alias kubectl="kubecolor"
    compdef kubecolor=kubectl
  fi

• fish

  # ~/.config/fish/config.fish
  if status is-interactive
    abbr --add k kubectl # https://fishshell.com/docs/current/cmds/abbr.html
  
    if  command -v kubecolor &>/dev/null
        alias kubectl=kubecolor # https://fishshell.com/docs/current/cmds/alias.html
  
        # make kubecolor inherit completions from kubectl # https://fishshell.com/docs/current/cmds/complete.html
        complete -c kubecolor -w kubectl
    end
  end

Switch between contexts (cluster) with kubectx

kubectx: a tool to switch between contexts (clusters) on kubectl faster.

Switch between namespaces with kubens

kubens: a tool to switch between Kubernetes namespaces (and configure them for kubectl) easily.

Switch between contexts/namspace with kubeswitch

kubeswitch: kubectx for operators, treat clusters as cattle, not pets.

Footnotes

1. https://github.com/headlamp-k8s/headlamp ↩

2. https://www.cncf.io/projects/headlamp/ ↩