K9s: Terminal UI for Navigating and Operating Kubernetes Clusters

Typing repetitive kubectl get pods, kubectl describe, and kubectl logs commands during an incident is slow and error-prone. K9s is a terminal-based UI (TUI) written in Go that provides a lightning-fast, keyboard-driven interface to observe, navigate, and manage Kubernetes clusters in real time.

K9s watches cluster resources via the Kubernetes API streaming channels, continuously refreshing views without manual re-runs while highlighting pod restarts, CPU/Memory throttling, and failed health probes.

flowchart TD
    subgraph Operator["SRE / DevOps Engineer"]
        Terminal["K9s Terminal UI (Vim-style navigation)"]
    end

    subgraph K9sEngine["K9s Core Architecture"]
        Watcher["Informer & Watch Engine (DeltaFIFO)"]
        ViewManager["View Manager (Pods, Deployments, Logs, Helm)"]
        PluginEngine["Custom Hotkey & Plugin System"]
        BenchmarkEngine["Integrated ApacheBench / Hey Load Tester"]
        
        Watcher --> ViewManager
        PluginEngine --> ViewManager
        BenchmarkEngine --> ViewManager
    end

    subgraph KubernetesCluster["Target Kubernetes Cluster"]
        KubeAPI["kube-apiserver"]
        Resources["Pods, Nodes, PVCs, CRDs, Events"]
        MetricsServer["metrics-server (CPU/RAM telemetry)"]
        
        Watcher <--> KubeAPI
        KubeAPI --> Resources
        KubeAPI --> MetricsServer
    end

    Terminal <--> K9sEngine

Essential K9s Keybindings and Workflows

K9s is designed for speed. Navigation follows intuitive Vim and shell conventions:

Keybinding	Action
`:pod`	Jump to Pods view across all namespaces
`:deploy`	Jump to Deployments view
`:sec`	Jump to Secrets view (auto-decodes base64 with `x`)
`:cr`	List all registered Custom Resource Definitions (CRDs)
`/query`	Filter resources matching a regex or text string
`<ctrl-d>`	Delete the selected resource (with confirmation modal)
`l`	Stream real-time logs for the selected pod or container
`s`	Open an interactive `exec` shell session into the selected pod
`d`	Run `kubectl describe` on the highlighted resource
`y`	View and edit the resource YAML live

Viewing Decoded Secrets Instantly

Instead of copying base64 strings and running echo "..." | base64 -d in a separate terminal:

Type :secret and press Enter.
Highlight your target Secret and press Enter.
Press x (toggle secret decoding) to view all key-value pairs in plaintext!

Customizing K9s with Plugins

K9s allows you to attach custom bash scripts and tools to single-letter hotkeys. Create ~/.config/k9s/plugins.yaml:

plugin:
  # Press 't' to open a Trivy vulnerability scan on the selected pod
  trivy:
    shortCut: Shift-T
    confirm: false
    description: "Trivy Scan"
    scopes:
      - pods
    command: trivy
    background: false
    args:
      - k8s
      - --report=summary
      - $NAMESPACE/$NAME

  # Press 'r' to trigger a rollout restart on the selected deployment
  restart:
    shortCut: Shift-R
    confirm: true
    description: "Rollout Restart"
    scopes:
      - deployments
    command: kubectl
    background: true
    args:
      - rollout
      - restart
      - deployment/$NAME
      - -n
      - $NAMESPACE

Port-Forwarding Without Complex Flags

To access an internal database or web service running inside your cluster:

Highlight the target Pod or Service in K9s.
Press Shift-F (Port Forward).
Specify the local port (e.g. 8080) and container port.
K9s manages the port-forward session in the background; view active forwards anytime by typing :portforward.

Production Power Tips

Skin & Color Profiles: Customize ~/.config/k9s/skins/ to assign high-visibility red themes to production cluster contexts to prevent accidental destructive actions.
Read-Only Mode: Run k9s --readonly when pairing with junior developers or presenting live demonstrations to disable all delete, edit, and restart mutations.
Context Switching: Type :ctx to switch instantly between AWS EKS, Google GKE, and local Kind cluster contexts without touching kubectx.