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https://github.com/derailed/k9s

๐Ÿถ Kubernetes CLI To Manage Your Clusters In Style!
https://github.com/derailed/k9s

go golang k8s k8s-cluster k9s kubernetes kubernetes-cli kubernetes-clusters

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๐Ÿถ Kubernetes CLI To Manage Your Clusters In Style!

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k9s



## K9s - Kubernetes CLI To Manage Your Clusters In Style!



K9s provides a terminal UI to interact with your Kubernetes clusters.

The aim of this project is to make it easier to navigate, observe and manage

your applications in the wild. K9s continually watches Kubernetes

for changes and offers subsequent commands to interact with your observed resources.



---



## Note...



K9s is not pimped out by a big corporation with deep pockets.

It is a complex OSS project that demands a lot of my time to maintain and support.

K9s will always remain OSS and therefore free! That said, if you feel k9s makes your day to day Kubernetes journey a tad brighter, saves you time and makes you more productive, please consider [sponsoring us!](https://github.com/sponsors/derailed)

Your donations will go a long way in keeping our servers lights on and beers in our fridge!



**Thank you!**



---



[![Go Report Card](https://goreportcard.com/badge/github.com/derailed/k9s?)](https://goreportcard.com/report/github.com/derailed/k9s)

[![golangci badge](https://github.com/golangci/golangci-web/blob/master/src/assets/images/badge_a_plus_flat.svg)](https://golangci.com/r/github.com/derailed/k9s)

[![codebeat badge](https://codebeat.co/badges/89e5a80e-dfe8-4426-acf6-6be781e0a12e)](https://codebeat.co/projects/github-com-derailed-k9s-master)

[![Build Status](https://travis-ci.com/derailed/k9s.svg?branch=master)](https://travis-ci.com/derailed/k9s)

[![Docker Repository on Quay](https://quay.io/repository/derailed/k9s/status "Docker Repository on Quay")](https://quay.io/repository/derailed/k9s)

[![release](https://img.shields.io/github/release-pre/derailed/k9s.svg)](https://github.com/derailed/k9s/releases)

[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/mum4k/termdash/blob/master/LICENSE)

[![Releases](https://img.shields.io/github/downloads/derailed/k9s/total.svg)](https://github.com/derailed/k9s/releases)



---



## Screenshots



1. Pods

      

2. Logs

      

3. Deployments

      



---



## Demo Videos/Recordings



* [K9s v0.30.0 Sneak peek](https://youtu.be/mVBc1XneRJ4)

* [Vulnerability Scans](https://youtu.be/ULkl0MsaidU)

* [K9s v0.29.0](https://youtu.be/oiU3wmoAkBo)

* [K9s v0.21.3](https://youtu.be/wG8KCwDAhnw)

* [K9s v0.19.X](https://youtu.be/kj-WverKZ24)

* [K9s v0.18.0](https://www.youtube.com/watch?v=zMnD5e53yRw)

* [K9s v0.17.0](https://www.youtube.com/watch?v=7S33CNLAofk&feature=youtu.be)

* [K9s Pulses](https://asciinema.org/a/UbXKPal6IWpTaVAjBBFmizcGN)

* [K9s v0.15.1](https://youtu.be/7Fx4XQ2ftpM)

* [K9s v0.13.0](https://www.youtube.com/watch?v=qaeR2iK7U0o&t=15s)

* [K9s v0.9.0](https://www.youtube.com/watch?v=bxKfqumjW4I)

* [K9s v0.7.0 Features](https://youtu.be/83jYehwlql8)

* [K9s v0 Demo](https://youtu.be/k7zseUhaXeU)



---



## Documentation



Please refer to our [K9s documentation](https://k9scli.io) site for installation, usage, customization and tips.



## Slack Channel



Wanna discuss K9s features with your fellow `K9sers` or simply show your support for this tool?



* Channel: [K9ersSlack](https://k9sers.slack.com/)

* Invite: [K9slackers Invite](https://join.slack.com/t/k9sers/shared_invite/enQtOTA5MDEyNzI5MTU0LWQ1ZGI3MzliYzZhZWEyNzYxYzA3NjE0YTk1YmFmNzViZjIyNzhkZGI0MmJjYzhlNjdlMGJhYzE2ZGU1NjkyNTM)



## Installation



K9s is available on Linux, macOS and Windows platforms.

Binaries for Linux, Windows and Mac are available as tarballs in the [release page](https://github.com/derailed/k9s/releases).



* Via [Homebrew](https://brew.sh/) for macOS or Linux



   ```shell

   brew install k9s

   ```



* Via [MacPorts](https://www.macports.org)



   ```shell

   sudo port install k9s

   ```



* Via [snap](https://snapcraft.io/k9s) for Linux



  ```shell

  snap install k9s --devmode

  ```



* On Arch Linux



  ```shell

  pacman -S k9s

  ```



* On OpenSUSE Linux distribution



  ```shell

  zypper install k9s

  ```



* On FreeBSD



  ```shell

  pkg install k9s

  ```



* Via [Winget](https://github.com/microsoft/winget-cli) for Windows



  ```shell

  winget install k9s

  ```



* Via [Scoop](https://scoop.sh) for Windows



  ```shell

  scoop install k9s

  ```



* Via [Chocolatey](https://chocolatey.org/packages/k9s) for Windows



  ```shell

  choco install k9s

  ```



* Via a GO install



  ```shell

  # NOTE: The dev version will be in effect!

  go install github.com/derailed/k9s@latest

  ```



* Via [Webi](https://webinstall.dev) for Linux and macOS



  ```shell

  curl -sS https://webinstall.dev/k9s | bash

  ```



* Via [pkgx](https://pkgx.dev/pkgs/k9scli.io/) for Linux and macOS



  ```shell

  pkgx k9s

  ```



* Via [Webi](https://webinstall.dev) for Windows



  ```shell

  curl.exe -A MS https://webinstall.dev/k9s | powershell

  ```



* As a [Docker Desktop Extension](https://docs.docker.com/desktop/extensions/) (for the Docker Desktop built in Kubernetes Server)



  ```shell

  docker extension install spurin/k9s-dd-extension:latest

  ```



---



## Building From Source



 K9s is currently using GO v1.21.X or above.

 In order to build K9s from source you must:



 1. Clone the repo

 2. Build and run the executable



      ```shell

      make build && ./execs/k9s

      ```



---



## Running with Docker



### Running the official Docker image



  You can run k9s as a Docker container by mounting your `KUBECONFIG`:



  ```shell

  docker run --rm -it -v $KUBECONFIG:/root/.kube/config quay.io/derailed/k9s

  ```



  For default path it would be:



  ```shell

  docker run --rm -it -v ~/.kube/config:/root/.kube/config quay.io/derailed/k9s

  ```



### Building your own Docker image



  You can build your own Docker image of k9s from the [Dockerfile](Dockerfile) with the following:



  ```shell

  docker build -t k9s-docker:v0.0.1 .

  ```



  You can get the latest stable `kubectl` version and pass it to the `docker build` command with the `--build-arg` option.

  You can use the `--build-arg` option to pass any valid `kubectl` version (like `v1.18.0` or `v1.19.1`).



  ```shell

  KUBECTL_VERSION=$(make kubectl-stable-version 2>/dev/null)

  docker build --build-arg KUBECTL_VERSION=${KUBECTL_VERSION} -t k9s-docker:0.1 .

  ```



  Run your container:



  ```shell

  docker run --rm -it -v ~/.kube/config:/root/.kube/config k9s-docker:0.1

  ```



---



## PreFlight Checks



* K9s uses 256 colors terminal mode. On `Nix system make sure TERM is set accordingly.



    ```shell

    export TERM=xterm-256color

    ```



* In order to issue resource edit commands make sure your EDITOR and KUBE_EDITOR env vars are set.



    ```shell

    # Kubectl edit command will use this env var.

    export KUBE_EDITOR=my_fav_editor

    ```



* K9s prefers recent kubernetes versions ie 1.28+



---



## K8S Compatibility Matrix



|         k9s        | k8s client |

| ------------------ | ---------- |

|     >= v0.27.0     |   1.26.1   |

| v0.26.7 - v0.26.6  |   1.25.3   |

| v0.26.5 - v0.26.4  |   1.25.1   |

| v0.26.3 - v0.26.1  |   1.24.3   |

| v0.26.0 - v0.25.19 |   1.24.2   |

| v0.25.18 - v0.25.3 |   1.22.3   |

| v0.25.2 - v0.25.0  |   1.22.0   |

|      <= v0.24      |   1.21.3   |



---



## The Command Line



```shell

# List current version

k9s version



# To get info about K9s runtime (logs, configs, etc..)

k9s info



# List all available CLI options

k9s help



# To run K9s in a given namespace

k9s -n mycoolns



# Start K9s in an existing KubeConfig context

k9s --context coolCtx



# Start K9s in readonly mode - with all cluster modification commands disabled

k9s --readonly

```



## Logs And Debug Logs



Given the nature of the ui k9s does produce logs to a specific location.

To view the logs and turn on debug mode, use the following commands:



```shell

# Find out where the logs are stored

k9s info

```



```text

 ____  __.________

|    |/ _/   __   \______

|      < \____    /  ___/

|    |  \   /    /\___ \

|____|__ \ /____//____  >

        \/            \/



Version:           vX.Y.Z

Config:            /Users/fernand/.config/k9s/config.yaml

Logs:              /Users/fernand/.local/state/k9s/k9s.log

Dumps dir:         /Users/fernand/.local/state/k9s/screen-dumps

Benchmarks dir:    /Users/fernand/.local/state/k9s/benchmarks

Skins dir:         /Users/fernand/.local/share/k9s/skins

Contexts dir:      /Users/fernand/.local/share/k9s/clusters

Custom views file: /Users/fernand/.local/share/k9s/views.yaml

Plugins file:      /Users/fernand/.local/share/k9s/plugins.yaml

Hotkeys file:      /Users/fernand/.local/share/k9s/hotkeys.yaml

Alias file:        /Users/fernand/.local/share/k9s/aliases.yaml

```



### View K9s logs



```shell

tail -f /Users/fernand/.local/data/k9s/k9s.log

```



### Start K9s in debug mode



```shell

k9s -l debug

```



### Customize logs destination



You can override the default log file destination either with the `--logFile` argument:



```shell

k9s --logFile /tmp/k9s.log

less /tmp/k9s.log

```



Or through the `K9S_LOGS_DIR` environment variable:



```shell

K9S_LOGS_DIR=/var/log k9s

less /var/log/k9s.log

```



## Key Bindings



K9s uses aliases to navigate most K8s resources.



| Action                                                                          | Command                       | Comment                                                                |

|---------------------------------------------------------------------------------|-------------------------------|------------------------------------------------------------------------|

| Show active keyboard mnemonics and help                                         | `?`                           |                                                                        |

| Show all available resource alias                                               | `ctrl-a`                      |                                                                        |

| To bail out of K9s                                                              | `:q`, `ctrl-c`                |                                                                        |

| View a Kubernetes resource using singular/plural or short-name                  | `:`podโŽ                       | accepts singular, plural, short-name or alias ie pod or pods           |

| View a Kubernetes resource in a given namespace                                 | `:`pod ns-xโŽ                  |                                                                        |

| View filtered pods (New v0.30.0!)                                               | `:`pod /fredโŽ                 | View all pods filtered by fred                                         |

| View labeled pods (New v0.30.0!)                                                | `:`pod app=fred,env=devโŽ      | View all pods with labels matching app=fred and env=dev                |

| View pods in a given context (New v0.30.0!)                                     | `:`pod @ctx1โŽ                 | View all pods in context ctx1. Switches out your current k9s context!  |

| Filter out a resource view given a filter                                       | `/`filterโŽ                    | Regex2 supported ie `fred|blee` to filter resources named fred or blee |

| Inverse regex filter                                                            | `/`! filterโŽ                  | Keep everything that *doesn't* match.                                  |

| Filter resource view by labels                                                  | `/`-l label-selectorโŽ         |                                                                        |

| Fuzzy find a resource given a filter                                            | `/`-f filterโŽ                 |                                                                        |

| Bails out of view/command/filter mode                                           | ``                       |                                                                        |

| Key mapping to describe, view, edit, view logs,...                              | `d`,`v`, `e`, `l`,...         |                                                                        |

| To view and switch to another Kubernetes context (Pod view)                     | `:`ctxโŽ                       |                                                                        |

| To view and switch directly to another Kubernetes context (Last used view)      | `:`ctx context-nameโŽ          |                                                                        |

| To view and switch to another Kubernetes namespace                              | `:`nsโŽ                        |                                                                        |

| To view all saved resources                                                     | `:`screendump or sdโŽ          |                                                                        |

| To delete a resource (TAB and ENTER to confirm)                                 | `ctrl-d`                      |                                                                        |

| To kill a resource (no confirmation dialog, equivalent to kubectl delete --now) | `ctrl-k`                      |                                                                        |

| Launch pulses view                                                              | `:`pulses or puโŽ              |                                                                        |

| Launch XRay view                                                                | `:`xray RESOURCE [NAMESPACE]โŽ | RESOURCE can be one of po, svc, dp, rs, sts, ds, NAMESPACE is optional |

| Launch Popeye view                                                              | `:`popeye or popโŽ             | See [popeye](#popeye)                                                  |



---



## K9s Configuration



  K9s keeps its configurations as YAML files inside of a `k9s` directory and the location depends on your operating system. K9s leverages [XDG](https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html) to load its various configurations files. For information on the default locations for your OS please see [this link](https://github.com/adrg/xdg/blob/master/README.md). If you are still confused a quick `k9s info` will reveal where k9s is loading its configurations from. Alternatively, you can set `K9S_CONFIG_DIR` to tell K9s the directory location to pull its configurations from.



  | Unix            | macOS                              | Windows               |

  |-----------------|------------------------------------|-----------------------|

  | `~/.config/k9s` | `~/Library/Application Support/k9s` | `%LOCALAPPDATA%\k9s`  |



  > NOTE: This is still in flux and will change while in pre-release stage!



  ```yaml

  # $XDG_CONFIG_HOME/k9s/config.yaml

  k9s:

    # Enable periodic refresh of resource browser windows. Default false

    liveViewAutoRefresh: false

    # The path to screen dump. Default: '%temp_dir%/k9s-screens-%username%' (k9s info)

    screenDumpDir: /tmp/dumps

    # Represents ui poll intervals. Default 2secs

    refreshRate: 2

    # Number of retries once the connection to the api-server is lost. Default 15.

    maxConnRetry: 5

    # Indicates whether modification commands like delete/kill/edit are disabled. Default is false

    readOnly: false

    # Toggles whether k9s should exit when CTRL-C is pressed. When set to true, you will need to exist k9s via the :quit command. Default is false.

    noExitOnCtrlC: false

    #UI settings

    ui:

      # Enable mouse support. Default false

      enableMouse: false

      # Set to true to hide K9s header. Default false

      headless: false

      # Set to true to hide the K9S logo Default false

      logoless: false

      # Set to true to hide K9s crumbs. Default false

      crumbsless: false

      noIcons: false

      # Toggles reactive UI. This option provide for watching on disk artifacts changes and update the UI live Defaults to false.

      reactive: false

      # By default all contexts wil use the dracula skin unless explicitly overridden in the context config file.

      skin: dracula # => assumes the file skins/dracula.yaml is present in the  $XDG_DATA_HOME/k9s/skins directory

      # Allows to set certain views default fullscreen mode. (yaml, helm history, describe, value_extender, details, logs) Default false

      defaultsToFullScreen: false

    # Toggles icons display as not all terminal support these chars.

    noIcons: false

    # Toggles whether k9s should check for the latest revision from the Github repository releases. Default is false.

    skipLatestRevCheck: false

    # When altering kubeconfig or using multiple kube configs, k9s will clean up clusters configurations that are no longer in use. Setting this flag to true will keep k9s from cleaning up inactive cluster configs. Defaults to false.

    keepMissingClusters: false

    # Logs configuration

    logger:

      # Defines the number of lines to return. Default 100

      tail: 200

      # Defines the total number of log lines to allow in the view. Default 1000

      buffer: 500

      # Represents how far to go back in the log timeline in seconds. Setting to -1 will tail logs. Default is -1.

      sinceSeconds: 300 # => tail the last 5 mins.

      # Toggles log line wrap. Default false

      textWrap: false

      # Toggles log line timestamp info. Default false

      showTime: false

    # Provide shell pod customization when nodeShell feature gate is enabled!

    shellPod:

      # The shell pod image to use.

      image: killerAdmin

      # The namespace to launch to shell pod into.

      namespace: default

      # The resource limit to set on the shell pod.

      limits:

        cpu: 100m

        memory: 100Mi

      # Enable TTY

      tty: true

  ```



---



## Popeye Configuration



K9s has integration with [Popeye](https://popeyecli.io/), which is a Kubernetes cluster sanitizer.  Popeye itself uses a configuration called `spinach.yml`, but when integrating with K9s the cluster-specific file should be name `$XDG_CONFIG_HOME/share/k9s/clusters/clusterX/contextY/spinach.yml`.  This allows you to have a different spinach config per cluster.



---



## Node Shell



By enabling the nodeShell feature gate on a given cluster, K9s allows you to shell into your cluster nodes. Once enabled, you will have a new `s` for `shell` menu option while in node view. K9s will launch a pod on the selected node using a special k9s_shell pod. Furthermore, you can refine your shell pod by using a custom docker image preloaded with the shell tools you love. By default k9s uses a BusyBox image, but you can configure it as follows:



```yaml

# $XDG_CONFIG_HOME/k9s/config.yaml

k9s:

  # You can also further tune the shell pod specification

  shellPod:

    image: cool_kid_admin:42

    namespace: blee

    limits:

      cpu: 100m

      memory: 100Mi

```



Then in your cluster configuration file...



```yaml

# $XDG_DATA_HOME/k9s/clusters/cluster-1/context-1

k9s:

  cluster: cluster-1

  readOnly: false

  namespace:

    active: default

    lockFavorites: false

    favorites:

    - kube-system

    - default

  view:

    active: po

  featureGates:

    nodeShell: true # => Enable this feature gate to make nodeShell available on this cluster

  portForwardAddress: localhost

```



---



## Command Aliases



In K9s, you can define your very own command aliases (shortnames) to access your resources. In your `$HOME/.config/k9s` define a file called `aliases.yaml`.

A K9s alias defines pairs of alias:gvr. A gvr (Group/Version/Resource) represents a fully qualified Kubernetes resource identifier. Here is an example of an alias file:



```yaml

#  $XDG_DATA_HOME/k9s/aliases.yaml

aliases:

  pp: v1/pods

  crb: rbac.authorization.k8s.io/v1/clusterrolebindings

  # As of v0.30.0 you can also refer to another command alias...

  fred: pod fred app=blee # => view pods in namespace fred with labels matching app=blee

```



Using this aliases file, you can now type `:pp` or `:crb` or `:fred` to activate their respective commands.



---



## HotKey Support



Entering the command mode and typing a resource name or alias, could be cumbersome for navigating thru often used resources.

We're introducing hotkeys that allow users to define their own key combination to activate their favorite resource views.



Additionally, you can define context specific hotkeys by add a context level configuration file in `$XDG_DATA_HOME/k9s/clusters/clusterX/contextY/hotkeys.yaml`



In order to surface hotkeys globally please follow these steps:



1. Create a file named `$XDG_CONFIG_HOME/k9s/hotkeys.yaml`

2. Add the following to your `hotkeys.yaml`. You can use resource name/short name to specify a command ie same as typing it while in command mode.



      ```yaml

      #  $XDG_CONFIG_HOME/k9s/hotkeys.yaml

      hotKeys:

        # Hitting Shift-0 navigates to your pod view

        shift-0:

          shortCut:    Shift-0

          description: Viewing pods

          command:     pods

        # Hitting Shift-1 navigates to your deployments

        shift-1:

          shortCut:    Shift-1

          description: View deployments

          command:     dp

        # Hitting Shift-2 navigates to your xray deployments

        shift-2:

          shortCut:    Shift-2

          description: Xray Deployments

          command:     xray deploy

        # Hitting Ctrl-U view the resources in the namespace of your current selection

        ctrl-u:

          shortCut:    Ctrl-U

          description: Namespaced resources

          command:     "$RESOURCE_NAME $NAMESPACE"

          keepHistory: true # whether you can return to the previous view

      ```



 Not feeling so hot? Your custom hotkeys will be listed in the help view `?`.

 Also your hotkeys file will be automatically reloaded so you can readily use your hotkeys as you define them.



 You can choose any keyboard shortcuts that make sense to you, provided they are not part of the standard K9s shortcuts list.



 Similarly, referencing environment variables in hotkeys is also supported. The available environment variables can refer to the description in the [Plugins](#plugins) section.



> NOTE: This feature/configuration might change in future releases!



---



## FastForwards



As of v0.25.0, you can leverage the `FastForwards` feature to tell K9s how to default port-forwards. In situations where you are dealing with multiple containers or containers exposing multiple ports, it can be cumbersome to specify the desired port-forward from the dialog as in most cases, you already know which container/port tuple you desire. For these use cases, you can now annotate your manifests with the following annotations:



@ `k9scli.io/auto-port-forwards`

  activates one or more port-forwards directly bypassing the port-forward dialog all together.

@ `k9scli.io/port-forwards`

  pre-selects one or more port-forwards when launching the port-forward dialog.



The annotation value takes on the shape `container-name::[local-port:]container-port`



> NOTE: for either cases above you can specify the container port by name or number in your annotation!



### Example



```yaml

# Pod fred

apiVersion: v1

kind: Pod

metadata:

  name: fred

  annotations:

    k9scli.io/auto-port-forwards: zorg::5556        # => will default to container zorg port 5556 and local port 5566. No port-forward dialog will be shown.

    # Or...

    k9scli.io/port-forwards: bozo::9090:p1          # => launches the port-forward dialog selecting default port-forward on container bozo port named p1(8081)

                                                    # mapping to local port 9090.

    ...

spec:

  containers:

  - name: zorg

    ports:

    - name: p1

      containerPort: 5556

    ...

  - name: bozo

    ports:

    - name: p1

      containerPort: 8081

    - name: p2

      containerPort: 5555

    ...

```



The annotation value must specify a container to forward to as well as a local port and container port. The container port may be specified as either a port number or port name. If the local port is omitted then the local port will default to the container port number. Here are a few examples:



1. bozo::http      - creates a pf on container `bozo` with port name http. If http specifies port number 8080 then the local port will be 8080 as well.

2. bozo::9090:http - creates a pf on container `bozo` mapping local port 9090->http(8080)

3. bozo::9090:8080 - creates a pf on container `bozo` mapping local port 9090->8080



---



## Resource Custom Columns



[SneakCast v0.17.0 on The Beach! - Yup! sound is sucking but what a setting!](https://youtu.be/7S33CNLAofk)



You can change which columns shows up for a given resource via custom views. To surface this feature, you will need to create a new configuration file, namely `$XDG_CONFIG_HOME/k9s/views.yaml`. This file leverages GVR (Group/Version/Resource) to configure the associated table view columns. If no GVR is found for a view the default rendering will take over (ie what we have now). Going wide will add all the remaining columns that are available on the given resource after your custom columns. To boot, you can edit your views config file and tune your resources views live!



> NOTE: This is experimental and will most likely change as we iron this out!



Here is a sample views configuration that customize a pods and services views.



```yaml

# $XDG_CONFIG_HOME/k9s/views.yaml

views:

  v1/pods:

    columns:

      - AGE

      - NAMESPACE

      - NAME

      - IP

      - NODE

      - STATUS

      - READY

  v1/services:

    columns:

      - AGE

      - NAMESPACE

      - NAME

      - TYPE

      - CLUSTER-IP

```



---



## Plugins



K9s allows you to extend your command line and tooling by defining your very own cluster commands via plugins. K9s will look at `$XDG_CONFIG_HOME/k9s/plugins.yaml` to locate all available plugins.



A plugin is defined as follows:



* Shortcut option represents the key combination a user would type to activate the plugin

* Confirm option (when enabled) lets you see the command that is going to be executed and gives you an option to confirm or prevent execution

* Description will be printed next to the shortcut in the k9s menu

* Scopes defines a collection of resources names/short-names for the views associated with the plugin. You can specify `all` to provide this shortcut for all views.

* Command represents ad-hoc commands the plugin runs upon activation

* Background specifies whether or not the command runs in the background

* Args specifies the various arguments that should apply to the command above



K9s does provide additional environment variables for you to customize your plugins arguments. Currently, the available environment variables are as follows:



* `$RESOURCE_GROUP` -- the selected resource group

* `$RESOURCE_VERSION` -- the selected resource api version

* `$RESOURCE_NAME` -- the selected resource name

* `$NAMESPACE` -- the selected resource namespace

* `$NAME` -- the selected resource name

* `$CONTAINER` -- the current container if applicable

* `$FILTER` -- the current filter if any

* `$KUBECONFIG` -- the KubeConfig location.

* `$CLUSTER` the active cluster name

* `$CONTEXT` the active context name

* `$USER` the active user

* `$GROUPS` the active groups

* `$POD` while in a container view

* `$COL-` use a given column name for a viewed resource. Must be prefixed by `COL-`!



Curly braces can be used to embed an environment variable inside another string, or if the column name contains special characters. (e.g. `${NAME}-example` or `${COL-%CPU/L}`)



### Plugin Example



This defines a plugin for viewing logs on a selected pod using `ctrl-l` as shortcut.



```yaml

#  $XDG_DATA_HOME/k9s/plugins.yaml

plugins:

  # Defines a plugin to provide a `ctrl-l` shortcut to tail the logs while in pod view.

  fred:

    shortCut: Ctrl-L

    confirm: false

    description: Pod logs

    scopes:

    - pods

    command: kubectl

    background: false

    args:

    - logs

    - -f

    - $NAME

    - -n

    - $NAMESPACE

    - --context

    - $CONTEXT

```



> NOTE: This is an experimental feature! Options and layout may change in future K9s releases as this feature solidifies.



---



## Benchmark Your Applications



K9s integrates [Hey](https://github.com/rakyll/hey) from the brilliant and super talented [Jaana Dogan](https://github.com/rakyll). `Hey` is a CLI tool to benchmark HTTP endpoints similar to AB bench. This preliminary feature currently supports benchmarking port-forwards and services (Read the paint on this is way fresh!).



To setup a port-forward, you will need to navigate to the PodView, select a pod and a container that exposes a given port. Using `SHIFT-F` a dialog comes up to allow you to specify a local port to forward. Once acknowledged, you can navigate to the PortForward view (alias `pf`) listing out your active port-forwards. Selecting a port-forward and using `CTRL-B` will run a benchmark on that HTTP endpoint. To view the results of your benchmark runs, go to the Benchmarks view (alias `be`). You should now be able to select a benchmark and view the run stats details by pressing ``. NOTE: Port-forwards only last for the duration of the K9s session and will be terminated upon exit.



Initially, the benchmarks will run with the following defaults:



* Concurrency Level: 1

* Number of Requests: 200

* HTTP Verb: GET

* Path: /



The PortForward view is backed by a new K9s config file namely: `$XDG_DATA_HOME/k9s/clusters/clusterX/contextY/benchmarks.yaml`. Each cluster you connect to will have its own bench config file, containing the name of the K8s context for the cluster. Changes to this file should automatically update the PortForward view to indicate how you want to run your benchmarks.



Benchmarks result reports are stored in `$XDG_STATE_HOME/k9s/clusters/clusterX/contextY`



Here is a sample benchmarks.yaml configuration. Please keep in mind this file will likely change in subsequent releases!



```yaml

# This file resides in  $XDG_DATA_HOME/k9s/clusters/clusterX/contextY/benchmarks.yaml

benchmarks:

  # Indicates the default concurrency and number of requests setting if a container or service rule does not match.

  defaults:

    # One concurrent connection

    concurrency: 1

    # Number of requests that will be sent to an endpoint

    requests: 500

  containers:

    # Containers section allows you to configure your http container's endpoints and benchmarking settings.

    # NOTE: the container ID syntax uses namespace/pod-name:container-name

    default/nginx:nginx:

      # Benchmark a container named nginx using POST HTTP verb using http://localhost:port/bozo URL and headers.

      concurrency: 1

      requests: 10000

      http:

        path: /bozo

        method: POST

        body:

          {"fred":"blee"}

        header:

          Accept:

            - text/html

          Content-Type:

            - application/json

  services:

    # Similarly you can Benchmark an HTTP service exposed either via NodePort, LoadBalancer types.

    # Service ID is ns/svc-name

    default/nginx:

      # Set the concurrency level

      concurrency: 5

      # Number of requests to be sent

      requests: 500

      http:

        method: GET

        # This setting will depend on whether service is NodePort or LoadBalancer. NodePort may require vendor port tunneling setting.

        # Set this to a node if NodePort or LB if applicable. IP or dns name.

        host: A.B.C.D

        path: /bumblebeetuna

      auth:

        user: jean-baptiste-emmanuel

        password: Zorg!

```



---



## K9s RBAC FU



On RBAC enabled clusters, you would need to give your users/groups capabilities so that they can use K9s to explore their Kubernetes cluster. K9s needs minimally read privileges at both the cluster and namespace level to display resources and metrics.



These rules below are just suggestions. You will need to customize them based on your environment policies. If you need to edit/delete resources extra Fu will be necessary.



> NOTE! Cluster/Namespace access may change in the future as K9s evolves.

> NOTE! We expect K9s to keep running even in atrophied clusters/namespaces. Please file issues if this is not the case!



### Cluster RBAC scope



```yaml

---

# K9s Reader ClusterRole

kind: ClusterRole

apiVersion: rbac.authorization.k8s.io/v1

metadata:

  name: k9s

rules:

  # Grants RO access to cluster resources node and namespace

  - apiGroups: [""]

    resources: ["nodes", "namespaces"]

    verbs: ["get", "list", "watch"]

  # Grants RO access to RBAC resources

  - apiGroups: ["rbac.authorization.k8s.io"]

    resources: ["clusterroles", "roles", "clusterrolebindings", "rolebindings"]

    verbs: ["get", "list", "watch"]

  # Grants RO access to CRD resources

  - apiGroups: ["apiextensions.k8s.io"]

    resources: ["customresourcedefinitions"]

    verbs: ["get", "list", "watch"]

  # Grants RO access to metric server (if present)

  - apiGroups: ["metrics.k8s.io"]

    resources: ["nodes", "pods"]

    verbs: ["get", "list", "watch"]



---

# Sample K9s user ClusterRoleBinding

apiVersion: rbac.authorization.k8s.io/v1

kind: ClusterRoleBinding

metadata:

  name: k9s

subjects:

  - kind: User

    name: fernand

    apiGroup: rbac.authorization.k8s.io

roleRef:

  kind: ClusterRole

  name: k9s

  apiGroup: rbac.authorization.k8s.io

```



### Namespace RBAC scope



If your users are constrained to certain namespaces, K9s will need to following role to enable read access to namespaced resources.



```yaml

---

# K9s Reader Role (default namespace)

kind: Role

apiVersion: rbac.authorization.k8s.io/v1

metadata:

  name: k9s

  namespace: default

rules:

  # Grants RO access to most namespaced resources

  - apiGroups: ["", "apps", "autoscaling", "batch", "extensions"]

    resources: ["*"]

    verbs: ["get", "list", "watch"]

  # Grants RO access to metric server

  - apiGroups: ["metrics.k8s.io"]

    resources: ["pods", "nodes"]

    verbs:

      - get

      - list

      - watch



---

# Sample K9s user RoleBinding

apiVersion: rbac.authorization.k8s.io/v1

kind: RoleBinding

metadata:

  name: k9s

  namespace: default

subjects:

  - kind: User

    name: fernand

    apiGroup: rbac.authorization.k8s.io

roleRef:

  kind: Role

  name: k9s

  apiGroup: rbac.authorization.k8s.io

```



---



## Skins



Example: Dracula Skin ;)



Dracula Skin



You can style K9s based on your own sense of look and style. Skins are YAML files, that enable a user to change the K9s presentation layer. See this repo `skins` directory for examples.

You can skin k9s by default by specifying a UI.skin attribute. You can also change K9s skins based on the context you are connecting too.

In this case, you can specify a skin field on your cluster config aka `skin: dracula` (just the name of the skin file without the extension!) and copy this repo

`skins/dracula.yaml` to `$XDG_CONFIG_HOME/k9s/skins/` directory.



In the case where your cluster spans several contexts, you can add a skin context configuration to your context configuration.

This is a collection of {context_name, skin} tuples (please see example below!)



Colors can be defined by name or using a hex representation. Of recent, we've added a color named `default` to indicate a transparent background color to preserve your terminal background color settings if so desired.



> NOTE: This is very much an experimental feature at this time, more will be added/modified if this feature has legs so thread accordingly!

> NOTE: Please see [K9s Skins](https://k9scli.io/topics/skins/) for a list of available colors.



To skin a specific context and provided the file `in_the_navy.yaml` is present in your skins directory.



```yaml

#  $XDG_DATA_HOME/k9s/clusters/clusterX/contextY/config.yaml

k9s:

  cluster: clusterX

  skin: in_the_navy

  readOnly: false

  namespace:

    active: default

    lockFavorites: false

    favorites:

    - kube-system

    - default

  view:

    active: po

  featureGates:

    nodeShell: false

  portForwardAddress: localhost

```



You can also specify a default skin for all contexts in the root k9s config file as so:



```yaml

#  $XDG_CONFIG_HOME/k9s/config.yaml

k9s:

  liveViewAutoRefresh: false

  screenDumpDir: /tmp/dumps

  refreshRate: 2

  maxConnRetry: 5

  readOnly: false

  noExitOnCtrlC: false

  ui:

    enableMouse: false

    headless: false

    logoless: false

    crumbsless: false

    noIcons: false

    # Toggles reactive UI. This option provide for watching on disk artifacts changes and update the UI live  Defaults to false.

    reactive: false

    # By default all contexts wil use the dracula skin unless explicitly overridden in the context config file.

    skin: dracula # => assumes the file skins/dracula.yaml is present in the  $XDG_DATA_HOME/k9s/skins directory

    defaultsToFullScreen: false

  skipLatestRevCheck: false

  disablePodCounting: false

  shellPod:

    image: busybox

    namespace: default

    limits:

      cpu: 100m

      memory: 100Mi

  imageScans:

    enable: false

    exclusions:

      namespaces: []

      labels: {}

  logger:

    tail: 100

    buffer: 5000

    sinceSeconds: -1

    textWrap: false

    showTime: false

  thresholds:

    cpu:

      critical: 90

      warn: 70

    memory:

      critical: 90

      warn: 70

```



```yaml

# $XDG_DATA_HOME/k9s/skins/in_the_navy.yaml

# Skin InTheNavy!

k9s:

  # General K9s styles

  body:

    fgColor: dodgerblue

    bgColor: '#ffffff'

    logoColor: '#0000ff'

  # ClusterInfoView styles.

  info:

    fgColor: lightskyblue

    sectionColor: steelblue

  # Help panel styles

  help:

    fgColor: white

    bgColor: black

    keyColor: cyan

    numKeyColor: blue

    sectionColor: gray

  frame:

    # Borders styles.

    border:

      fgColor: dodgerblue

      focusColor: aliceblue

    # MenuView attributes and styles.

    menu:

      fgColor: darkblue

      keyColor: cornflowerblue

      # Used for favorite namespaces

      numKeyColor: cadetblue

    # CrumbView attributes for history navigation.

    crumbs:

      fgColor: white

      bgColor: steelblue

      activeColor: skyblue

    # Resource status and update styles

    status:

      newColor: '#00ff00'

      modifyColor: powderblue

      addColor: lightskyblue

      errorColor: indianred

      highlightcolor: royalblue

      killColor: slategray

      completedColor: gray

    # Border title styles.

    title:

      fgColor: aqua

      bgColor: white

      highlightColor: skyblue

      counterColor: slateblue

      filterColor: slategray

  views:

    # TableView attributes.

    table:

      fgColor: blue

      bgColor: darkblue

      cursorColor: aqua

      # Header row styles.

      header:

        fgColor: white

        bgColor: darkblue

        sorterColor: orange

    # YAML info styles.

    yaml:

      keyColor: steelblue

      colonColor: blue

      valueColor: royalblue

    # Logs styles.

    logs:

      fgColor: lightskyblue

      bgColor: black

      indicator:

        fgColor: dodgerblue

        bgColor: black

        toggleOnColor: limegreen

        toggleOffColor: gray

```



---



## Contributors



Without the contributions from these fine folks, this project would be a total dud!





  




---



## Known Issues



This is still work in progress! If something is broken or there's a feature

that you want, please file an issue and if so inclined submit a PR!



K9s will most likely blow up if...



1. You're running older versions of Kubernetes. K9s works best on later Kubernetes versions.

2. You don't have enough RBAC fu to manage your cluster.



---



## ATTA Girls/Boys!



K9s sits on top of many open source projects and libraries. Our *sincere*

appreciations to all the OSS contributors that work nights and weekends

to make this project a reality!



---



## Meet The Core Team!



* [Fernand Galiana](https://github.com/derailed)

  * email  [email protected]

  * twitter [@kitesurfer](https://twitter.com/kitesurfer?lang=en)



* [Aleksei Romanenko](https://github.com/slimus)



We always enjoy hearing from folks who benefit from our work!



## Contributions Guideline



* File an issue first prior to submitting a PR!

* Ensure all exported items are properly commented

* If applicable, submit a test suite against your PR



---



Imhotep ย ยฉ 2023 Imhotep Software LLC. All materials licensed under [Apache v2.0](http://www.apache.org/licenses/LICENSE-2.0)