[쿠버네티스] KIND(K8s IN Docker) 설치하기

Kubernetes IN Docker

What is KIND?

도커 컨테이너 노드를 사용하여 로컬 쿠버네티스 클러스터를 실행하는 도구

 

KIND의 주요 특징(출처: KIND 공식)

1. 로컬 클러스터 실행
   Docker 컨테이너를 노드로 사용하여, 가볍고 빠르게 클러스터 실행 가능하다.
2. 쿠버네티스 테스트
   쿠버네티스 개발자들이 새로운 기능이나 버전을 테스트할 수 있도록 설계되었다.
3. CI/CD 환경 적합
   빠른 클러스터 생성·삭제로 자동화된 테스트에 적합하다.
4. 멀티 노드 지원
   여러 노드(마스터/워커)를 포함한 클러스터 구성이 가능하다.
5. 경량화된 환경
   VM 없이 Docker만 있으면 실행 가능하다.

 

KIND 설치하기(출처: KIND 공식)

#KIND 설치
#curl -Lo 다운받을경로 설치URL
[root@]$ curl -Lo ./kind https://kind.sigs.k8s.io/dl/v0.11.1/kind-linux-amd64
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100    97  100    97    0     0    177      0 --:--:-- --:--:-- --:--:--   176
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100 6660k  100 6660k    0     0  3333k      0  0:00:01  0:00:01 --:--:-- 80.3M

 

#다운받은폴더에 권한부여
[root@]$ chmod +x ./kind

 

#다운받은 디렉토리를 /usr/local/bin 하위로 옮긴다
#/usr/local/bin 하위로 이동시켜야 kind 커맨드가 실행된다
[root@]$ mv ./kind /usr/local/bin/kind

 

#kind 명령어 실행 확인
[root@]$ kind
kind creates and manages local Kubernetes clusters using Docker container 'nodes'

Usage:
  kind [command]

Available Commands:
  build       Build one of [node-image]
  completion  Output shell completion code for the specified shell (bash, zsh or fish)
  create      Creates one of [cluster]
  delete      Deletes one of [cluster]
  export      Exports one of [kubeconfig, logs]
  get         Gets one of [clusters, nodes, kubeconfig]
  help        Help about any command
  load        Loads images into nodes
  version     Prints the kind CLI version

Flags:
  -h, --help              help for kind
      --loglevel string   DEPRECATED: see -v instead
  -q, --quiet             silence all stderr output
  -v, --verbosity int32   info log verbosity
      --version           version for kind

Use "kind [command] --help" for more information about a command.

 

#kubectl 설치하기
#KIND는 Cluster가 생성될 때, kubectl과 연결되도록 ~/.kube/config 파일에 설정이 추가된다.
#Cluster를 설치한 후, kubectl을 설치하면 정상적으로 연결이 되지 않으므로 kubectl을 먼저 설치한다.
[root@]$ curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   138  100   138    0     0    594      0 --:--:-- --:--:-- --:--:--   594
100 57.3M  100 57.3M    0     0  65.0M      0 --:--:-- --:--:-- --:--:-- 65.0M

 

#다운받은 kubectl을 /usr/local/bin 하위로 옮긴다
[root@]$ install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl

[root@]$ kubectl
kubectl controls the Kubernetes cluster manager.

 Find more information at: https://kubernetes.io/docs/reference/kubectl/

Basic Commands (Beginner):
  create          Create a resource from a file or from stdin
  expose          Take a replication controller, service, deployment or pod and expose it as a new Kubernetes service
  run             Run a particular image on the cluster
  set             Set specific features on objects

Basic Commands (Intermediate):
  explain         Get documentation for a resource
  get             Display one or many resources
  edit            Edit a resource on the server
  delete          Delete resources by file names, stdin, resources and names, or by resources and label selector

Deploy Commands:
  rollout         Manage the rollout of a resource
  scale           Set a new size for a deployment, replica set, or replication controller
  autoscale       Auto-scale a deployment, replica set, stateful set, or replication controller

Cluster Management Commands:
  certificate     Modify certificate resources
  cluster-info    Display cluster information
  top             Display resource (CPU/memory) usage
  cordon          Mark node as unschedulable
  uncordon        Mark node as schedulable
  drain           Drain node in preparation for maintenance
  taint           Update the taints on one or more nodes

Troubleshooting and Debugging Commands:
  describe        Show details of a specific resource or group of resources
  logs            Print the logs for a container in a pod
  attach          Attach to a running container
  exec            Execute a command in a container
  port-forward    Forward one or more local ports to a pod
  proxy           Run a proxy to the Kubernetes API server
  cp              Copy files and directories to and from containers
  auth            Inspect authorization
  debug           Create debugging sessions for troubleshooting workloads and nodes
  events          List events

Advanced Commands:
  diff            Diff the live version against a would-be applied version
  apply           Apply a configuration to a resource by file name or stdin
  patch           Update fields of a resource
  replace         Replace a resource by file name or stdin
  wait            Experimental: Wait for a specific condition on one or many resources
  kustomize       Build a kustomization target from a directory or URL

Settings Commands:
  label           Update the labels on a resource
  annotate        자원에 대한 주석을 업데이트합니다
  completion      Output shell completion code for the specified shell (bash, zsh, fish, or powershell)

Subcommands provided by plugins:

Other Commands:
  api-resources   Print the supported API resources on the server
  api-versions    Print the supported API versions on the server, in the form of "group/version"
  config          kubeconfig 파일을 수정합니다
  plugin          Provides utilities for interacting with plugins
  version         Print the client and server version information

Usage:
  kubectl [flags] [options]

Use "kubectl <command> --help" for more information about a given command.
Use "kubectl options" for a list of global command-line options (applies to all commands).

 

#클러스터 생성하기
#kind create cluster --name 클러스터이름
[root@]$ kind create cluster --name my-cluster

Creating cluster "my-cluster" ...
 ✓ Ensuring node image (kindest/node:v1.21.1) 🖼
 ✓ Preparing nodes 📦
 ✓ Writing configuration 📜
 ✓ Starting control-plane 🕹️
 ✓ Installing CNI 🔌
 ✓ Installing StorageClass 💾
Set kubectl context to "kind-my-cluster"
You can now use your cluster with:

kubectl cluster-info --context kind-my-cluster

Thanks for using kind! 😊

 

#클러스터 생성 확인하기
#kind get clusters
[root@]$ kind get clusters
my-cluster

#kubectl을 사용해 클러스터 생성 확인
[root@]$ kubectl cluster-info --context kind-my-cluster
Kubernetes control plane is running at https://127.0.0.1:42395
CoreDNS is running at https://127.0.0.1:42395/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.


#리소스 생성 확인
#노드와 서비스가 1개씩 기본 생성된 것을 확인한다
[root@]$ kubectl get nodes
NAME                 STATUS   ROLES                  AGE   VERSION
bxbu-control-plane   Ready    control-plane,master   10m   v1.21.1

[root@]$ kubectl get all
NAME                 TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
service/kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP   3m27s

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