K9s

K9s is a terminal-based UI to interact with Kubernetes clusters, making it easier to navigate, observe, and manage deployed applications. It continuously watches Kubernetes for changes and offers commands to interact with resources.

CLI Arguments🔗

Basic Commands🔗

# Launch K9s
k9s

# Show help and available options
k9s help

# Get info about K9s runtime (logs, configs, etc.)
k9s info

# Run K9s in a specific namespace
k9s -n my-namespace

# Launch K9s directly in pod view
k9s -c pod

# Start K9s in a different context
k9s --context my-context

# Start K9s in readonly mode (no modifications allowed)
k9s --readonly

Essential Key Bindings🔗

Key	Action	Description
`?`	Show help	Display active keyboard shortcuts and help
`Ctrl+a`	Show aliases	List all available resource aliases
`:q` or `Ctrl+c`	Exit	Quit K9s
`Esc`	Back/Cancel	Exit current view/command/filter mode

Command	Action	Example
`:pod⏎`	View pods	Shows all pods (accepts singular/plural/short names)
`:deploy⏎`	View deployments	Shows all deployments
`:svc⏎`	View services	Shows all services
`:ns⏎`	View namespaces	Shows and allows switching namespaces
`:ctx⏎`	View contexts	Shows and allows switching contexts

Namespace & Context Operations🔗

# View pods in specific namespace
:pod my-namespace⏎

# View pods with specific context
:pod @my-context⏎

# Switch to namespace and keep current view
:ns my-namespace⏎

# Switch to context and keep current view  
:ctx my-context⏎

Filtering & Search🔗

Command	Action	Example
`/filter⏎`	Filter resources	`/nginx⏎` shows resources containing “nginx”
`/!filter⏎`	Inverse filter	`/!system⏎` excludes resources containing “system”
`/-l label⏎`	Filter by labels	`/-l app=nginx⏎`
`/-f filter⏎`	Fuzzy search	`/-f web⏎` fuzzy finds “web”

Label-based Filtering🔗

# View pods with specific labels
:pod app=nginx,env=prod⏎

# View pods in namespace with labels
:pod my-namespace app=web⏎

# Filter current view by labels
/-l app=nginx,tier=frontend⏎

Resource Management🔗

Common Resource Actions🔗

Key	Action	Description
`d`	Describe	Show detailed resource information
`v`	View YAML	Display resource YAML definition
`e`	Edit	Edit resource (opens in $KUBE_EDITOR)
`l`	Logs	View container logs
`s`	Shell	Shell into container
`f`	Port-forward	Forward local port to pod

Resource Lifecycle🔗

Key	Action	Description
`Ctrl+d`	Delete	Delete resource (with confirmation)
`Ctrl+k`	Kill	Force delete resource (no confirmation)
`r`	Restart	Restart resource (deployments, etc.)

Advanced Views🔗

Command	Action	Description
`:pulses⏎` or `:pu⏎`	Pulses view	Cluster dashboard overview
`:xray pod⏎`	XRay view	Resource dependency visualization
`:screendump⏎` or `:sd⏎`	Screen dump	View saved resources

Configuration🔗

Main Config File🔗

Location: $XDG_CONFIG_HOME/k9s/config.yaml (usually ~/.config/k9s/config.yaml)

# ~/.config/k9s/config.yaml
k9s:
  # UI refresh rate in seconds
  refreshRate: 2
  
  # Enable auto-refresh of resource views
  liveViewAutoRefresh: false
  
  # API server timeout
  apiServerTimeout: 15s
  
  # Max connection retries
  maxConnRetry: 5
  
  # Disable modification commands
  readOnly: false
  
  # Default view on startup
  defaultView: "pods"
  
  # Exit on Ctrl+C (false means use :quit command)
  noExitOnCtrlC: false
  
  # Port forward default address
  portForwardAddress: localhost
  
  ui:
    # Enable mouse support
    enableMouse: false
    
    # Hide header/logo/crumbs
    headless: false
    logoless: false
    crumbsless: false
    
    # Live update UI on config changes
    reactive: false
    
    # Disable icons for unsupported terminals
    noIcons: false
  
  # Skip version check
  skipLatestRevCheck: false
  
  # Logs configuration
  logger:
    # Number of log lines to show
    tail: 100
    # Total log buffer size
    buffer: 5000
    # How far back to look in seconds (-1 for tail)
    sinceSeconds: 300
    # Full screen logs
    fullScreen: false
    # Wrap long lines
    textWrap: false
    # Show timestamps
    showTime: false
  
  # Resource thresholds for alerts
  thresholds:
    cpu:
      critical: 90
      warn: 70
    memory:
      critical: 90
      warn: 70

Context-Specific Configuration🔗

Location: $XDG_DATA_HOME/k9s/clusters/{cluster}/{context}/config.yaml

# Context-specific config
k9s:
  cluster: my-cluster
  readOnly: false
  skin: my_custom_skin
  
  namespace:
    active: default
    lockFavorites: false
    favorites:
      - all
      - kube-system
      - default
      - my-app
  
  view:
    active: pods
  
  featureGates:
    nodeShell: true

Aliases🔗

Creating Custom Aliases🔗

File: $XDG_CONFIG_HOME/k9s/aliases.yaml

# ~/.config/k9s/aliases.yaml
aliases:
  # Resource aliases
  pp: v1/pods                          # Use :pp instead of :pods
  dep: apps/v1/deployments            # Use :dep instead of :deployments
  svc: v1/services                    # Use :svc instead of :services
  ing: networking.k8s.io/v1/ingresses # Use :ing instead of :ingresses
  
  # Custom resource aliases
  fred: acme.io/v1alpha1/fredericks   # Custom CRD alias
  
  # Command aliases with filters
  web-pods: pod default app=web                    # Pods with app=web label
  sys-pods: pod kube-system                       # All kube-system pods
  nginx-ing: ingress default app=nginx            # Nginx ingresses
  critical-pods: pod -l priority=critical         # High priority pods

Using Aliases🔗

# Use aliases in command mode
:pp⏎              # List pods
:dep⏎             # List deployments  
:web-pods⏎        # List web application pods
:sys-pods⏎        # List system pods

HotKeys🔗

Creating Custom HotKeys🔗

File: $XDG_DATA_HOME/k9s/hotkeys.yaml

# ~/.local/share/k9s/hotkeys.yaml
hotKeys:
  # Quick navigation shortcuts
  shift-1:
    shortCut: Shift-1
    description: View all pods
    command: pods
  
  shift-2:
    shortCut: Shift-2
    description: View deployments
    command: deployments
  
  shift-3:
    shortCut: Shift-3
    description: View services
    command: services
  
  # Filtered views
  shift-w:
    shortCut: Shift-w
    description: Web application pods
    command: pods app=web
  
  shift-s:
    shortCut: Shift-s
    description: System pods
    command: pods kube-system
  
  # XRay views
  shift-x:
    shortCut: Shift-x
    description: XRay deployments
    command: xray deploy
  
  # Custom namespace shortcuts
  shift-p:
    shortCut: Shift-p
    description: Production namespace
    command: pods production

Advanced Features🔗

XRay Views🔗

# Visualize resource dependencies
:xray pod my-namespace⏎       # Pod dependencies
:xray svc⏎                    # Service dependencies  
:xray deploy⏎                 # Deployment dependencies
:xray sts⏎                    # StatefulSet dependencies

Pulses Dashboard🔗

# Launch cluster overview dashboard
:pulses⏎
:pu⏎

Log Management🔗

# View logs with different options
l                             # View logs (from resource view)
Ctrl+t                        # Toggle timestamp in logs
Ctrl+w                        # Toggle line wrap in logs

Port Forwarding🔗

# Forward ports (from pod view)
f                             # Start port forward
# Then specify: local_port:remote_port
8080:80                       # Forward local 8080 to pod port 80

Shell Access🔗

# Shell into containers
s                             # Shell into container
# Select container if multiple containers in pod

Environment Variables🔗

Global Overrides🔗

# Override default port forward address
export K9S_DEFAULT_PF_ADDRESS=127.0.0.1

# Override node shell feature globally
export K9S_FEATURE_GATE_NODE_SHELL=true

# Set custom config directory
export K9S_CONFIG_DIR=/path/to/config

# Set XDG directories
export XDG_CONFIG_HOME=$HOME/.config
export XDG_DATA_HOME=$HOME/.local/share

Practical Examples🔗

Daily Workflow Examples🔗

1. Quick Pod Debugging🔗

# Launch K9s in pod view
k9s -c pod

# Filter to problematic pods
/error⏎

# Describe a pod
d

# View logs
l

# Shell into container
s

2. Deployment Management🔗

# View deployments
:deploy⏎

# Filter by namespace
:deploy my-app⏎

# Scale deployment (edit and change replicas)
e

# Restart deployment
r

# View deployment logs
l

3. Resource Monitoring🔗

# Launch pulses for cluster overview
:pulses⏎

# Check resource usage
:top node⏎
:top pod⏎

# Filter high CPU usage
/-l cpu>80⏎

4. Multi-Context Management🔗

# Switch contexts
:ctx⏎
# Select context from list

# View contexts with direct switch
:ctx production⏎

# Launch in specific context
k9s --context staging

Troubleshooting Workflows🔗

1. Find Failing Pods🔗

# Filter by status
/Error⏎
/CrashLoop⏎
/Pending⏎

# Or use labels to find specific app pods
/-l app=myapp⏎

# Describe to see events
d

# Check logs for errors
l

2. Resource Dependencies🔗

# Use XRay to see dependencies
:xray pod my-namespace⏎

# Navigate through related resources
# Follow ingress -> service -> deployment -> pod chain

3. Network Debugging🔗

# View services
:svc⏎

# Check endpoints
:ep⏎

# View ingresses
:ing⏎

# Port forward for testing
f
# Test: curl localhost:8080

Tips & Best Practices🔗

Performance Tips🔗

Use liveViewAutoRefresh: false for large clusters
Adjust refreshRate based on cluster size
Use filters to reduce displayed resources
Enable disablePodCounting for very large clusters

Security Tips🔗

Use readOnly: true for production environments
Set context-specific readonly configs
Use RBAC to limit K9s permissions
Regularly audit your cluster access

Customization Tips🔗

Create aliases for frequently used commands
Set up hotkeys for common workflows
Use custom skins for different environments
Configure context-specific settings

Efficiency Tips🔗

Learn regex patterns for complex filtering
Use label selectors for precise filtering
Master XRay views for dependency tracking
Customize column views for important metrics

Common Issues & Solutions🔗

Terminal Issues🔗

# Fix color issues
export TERM=xterm-256color

# Fix editor issues
export KUBE_EDITOR=vim

Permission Issues🔗

# Check K9s permissions
k9s info

# Verify kubectl access
kubectl auth can-i --list

Configuration Issues🔗

# Check config location
k9s info

# Reset configuration
rm -rf ~/.config/k9s
rm -rf ~/.local/share/k9s

Resources🔗

Official Website: https://k9scli.io/
GitHub Repository: https://github.com/derailed/k9s
Community Slack: K9ers Slack
Documentation: https://k9scli.io/topics/
Video Tutorials: https://k9scli.io/topics/video/

K9s makes Kubernetes cluster management intuitive and efficient through its terminal-based interface. Master these commands and configurations to significantly improve your Kubernetes workflow.