Using rancher to build kubernetes cluster

Rancher build Kubernetes colony

kubernetes There are many ways to deploy , The main known are kind、minikube、kubeadm、 Binary package 、Rancher

Official website ：https://kubernetes.io/zh/

The Chinese community : https://www.kubernetes.org.cn/

Rancher summary

Rancher It is an open source enterprise container management platform . Use Rancher, There is no need to build a container service platform from scratch .

Rancher Provides management for use in production environments Docker and Kubernetes Full stack container deployment and management platform .

Rancher yes K8S Visual management tools ,Rancher Built in K8S, No additional installation is required , Use it directly .

Rancher Installation

Pull the mirror image

docker pull rancher/rancher:v2.5.12

Start the container

docker run -p 80:80 -p 443:443 --name rancher --restart=unless-stopped --privileged -d rancher/rancher:v2.5.12

Be careful ：Rancher 2.5.x And later , Need to add –privileged Flag variable , Enable privileged mode installation

Rancher Initial configuration and overview of

visit Rancher The home page of , The first time you need to set up an administrator (admin) Account and password

Set up Rancher Of Server URL, other Node Can be accessed to the address

Get into Rancher home page , Installed by default k3s The cluster of

Click the cluster name to view the cluster status information

Click the dashboard button , View the various features of the cluster Dashboard

Rancher Application deployment

Mode one

Fill in the form information for deployment

Import YAML File deployment

Mode two

1. establish Deployment object

find Deployments->Create-> Edit as YAML


Fill in deployment.yaml Information

2. establish Service Expose port information


Fill in service.yaml Information

Rancher Deploy MySQL application

establish Deployment

# API edition 
apiVersion: apps/v1
# API object type 
kind: Deployment
metadata:
  #  Appoint Deployment The name of 
  name: mysql-deployment
  #  Appoint Deployment Space , Otherwise, it cannot be created 
  namespace: default
  #  Appoint Deployment The label of  
  labels:
    app: mysql
spec:
  #  Specify the created Pod Copy number  
  replicas: 1
  #  Define how to find the Pod
  selector:
    #  Manage tags app by mysql Of Pod
    matchLabels:
      app: mysql
  #  Specify create Pod The template of 
  template:
    metadata:
      #  to Pod In the play app:mysql label 
      labels:
        app: mysql
    # Pod Template specification for 
    spec:
      containers:
        - name: mysql
          #  Specify the container image 
          image: mysql:5.7
          #  Specify the open port 
          ports:
            - containerPort: 3306
          #  Set the environment variable 
          env:
            - name: MYSQL_ROOT_PASSWORD
              value: root123456
          #  Using a storage volume 
          volumeMounts:
            #  Mount the storage volume to the internal path of the container 
            - mountPath: /var/log/mysql
              name: log-volume
            - mountPath: /var/lib/mysql
              name: data-volume
            - mountPath: /etc/mysql
              name: conf-volume
      #  Define storage volumes 
      volumes:
        - name: log-volume
          # hostPath Type the path of the storage volume on the host 
          hostPath:
            path: /usr/local/program/mysql/log
            #  Create when directory doesn't exist 
            type: DirectoryOrCreate
        - name: data-volume
          hostPath:
            path: /usr/local/program/mysql/data
            type: DirectoryOrCreate
        - name: conf-volume
          hostPath:
            path: /usr/local/program/mysql/conf
            type: DirectoryOrCreate

establish Service

apiVersion: v1
kind: Service
metadata:
  #  Defining space 
  namespace: default
  #  Define service name , other Pod It can be accessed as a domain name through the service name 
  name: mysql-service
spec:
  #  Specify service type , adopt Node Static port exposure service on 
  type: NodePort
  #  Manage tags app by mysql Of Pod
  selector:
    app: mysql
  ports:
    - name: http
      protocol: TCP
      port: 3307
      targetPort: 3306
      # Node Static port on 
      nodePort: 30303

Access test

obtain Rancher Containers IP Address

[[email protected] ~]# docker inspect rancher |grep IPAddress
            "SecondaryIPAddresses": null,
            "IPAddress": "172.17.0.2",
                    "IPAddress": "172.17.0.2",

Connect to database

[[email protected] ~]# mysql -h 172.17.0.2 -P 30303 -uroot -proot123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.37 MySQL Community Server (GPL)

Copyright (c) 2000, 2021, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

Rancher Deploy SpringBoot application

establish Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  namespace: default
  name: jar-deployment
  labels:
    app: jar-test
spec:
  replicas: 1
  selector:
    matchLabels:
      app: jar-test
  template:
    metadata:
      labels:
        app: jar-test
    spec:
      containers:
        - name: jar-name
          #  Appoint Docker Hub Image address in 
          image: IP/jar-test:0.0.1-SNAPSHOT
          ports:
            - containerPort: 8080
          env:
            #  Specify the database connection address 
            - name: spring.datasource.url
              value: jdbc:mysql://mysql-service:3307/demo?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
            - name: logging.path
              value: /var/logs
          volumeMounts:
            - mountPath: /var/logs
              name: log-volume
      volumes:
        - name: log-volume
          hostPath:
            path: /usr/local/program/app/logs
            type: DirectoryOrCreate

establish Service

apiVersion: v1
kind: Service
metadata:
  namespace: default
  name: jar-service
spec:
  type: NodePort
  selector:
    app: jar-test
  ports:
    - name: http
      protocol: TCP
      port: 8080
      targetPort: 8080
      # Node Static port on 
      nodePort: 30001

Access test

curl http://172.17.0.2:30001index.html

Add clusters

stay master The node runs the command import rancher

Kubernetes Basic operation

Application deployment

Create a name nginx-test Of Deployment, Also specify the application image

kubectl create deployment nginx-test --image=nginx

View all Deployment：kubectl get deployments

NAME         READY   UP-TO-DATE   AVAILABLE   AGE
nginx-test   1/1     1            1           18s

Delete deployment Application

kubectl delete deployment  nginx-test

View application information

View all Pod The state of ：kubectl get pods

NAME                          READY   STATUS    RESTARTS   AGE
nginx-test-84b478f9c5-vz7bw   1/1     Running   0          29s

see Pod Detailed state :kubectl describe pods

Name:         nginx-test-84b478f9c5-vz7bw
Namespace:    default
Priority:     0
Node:         minikube/192.168.49.2
Start Time:   Tue, 22 Mar 2022 09:03:09 +0800
Labels:       app=nginx-test
              pod-template-hash=84b478f9c5
Annotations:  <none>
Status:       Running
IP:           172.17.0.3
IPs:
  IP:           172.17.0.3
Controlled By:  ReplicaSet/nginx-test-84b478f9c5
Containers:
  nginx:
    Container ID:   docker://8f20af263a8c7dce564fa6d49943fbef4fe151aaaef24e3564e57e13787c7213
    Image:          nginx
    Image ID:       docker-pullable://[email protected]:e1211ac17b29b585ed1aee166a17fad63d344bc973bc63849d74c6452d549b3e
    Port:           <none>
    Host Port:      <none>
    State:          Running
      Started:      Tue, 22 Mar 2022 09:03:13 +0800
    Ready:          True
    Restart Count:  0
    Environment:    <none>
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-2hldl (ro)
Conditions:
  Type              Status
  Initialized       True
  Ready             True
  ContainersReady   True
  PodScheduled      True
Volumes:
  kube-api-access-2hldl:
    Type:                    Projected (a volume that contains injected data from multiple sources)
    TokenExpirationSeconds:  3607
    ConfigMapName:           kube-root-ca.crt
    ConfigMapOptional:       <nil>
    DownwardAPI:             true
QoS Class:                   BestEffort
Node-Selectors:              <none>
Tolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                             node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type    Reason     Age   From               Message
  ----    ------     ----  ----               -------
  Normal  Scheduled  39s   default-scheduler  Successfully assigned default/nginx-test-84b478f9c5-vz7bw to minikube
  Normal  Pulling    39s   kubelet            Pulling image "nginx"
  Normal  Pulled     36s   kubelet            Successfully pulled image "nginx" in 2.952573727s
  Normal  Created    35s   kubelet            Created container nginx
  Normal  Started    35s   kubelet            Started container nginx

take Pod Set the name to the environment variable , Easy to use $POD_NAME To apply Pod The name of

export NGINX_POD=nginx-test-84b478f9c5-vz7bw

see Pod Printed logs ：kubectl logs $NGINX_POD

/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up
2022/03/22 01:03:13 [notice] 1#1: using the "epoll" event method
2022/03/22 01:03:13 [notice] 1#1: nginx/1.21.6
2022/03/22 01:03:13 [notice] 1#1: built by gcc 10.2.1 20210110 (Debian 10.2.1-6)
2022/03/22 01:03:13 [notice] 1#1: OS: Linux 3.10.0-1160.59.1.el7.x86_64
2022/03/22 01:03:13 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2022/03/22 01:03:13 [notice] 1#1: start worker processes
2022/03/22 01:03:13 [notice] 1#1: start worker process 32
2022/03/22 01:03:13 [notice] 1#1: start worker process 33

Use exec stay Pod Execute commands in the container of

kubectl exec nginx-test-84b478f9c5-vz7bw -- echo hello world

Go inside the container and execute bash command , Exit container exit command

kubectl exec -it nginx-test-84b478f9c5-vz7bw  -- bash

Public exposure applications

Default Pod Cannot be accessed outside the cluster , Need to create Service And expose the port to be accessed externally .

establish Service expose nginx-test This Deployment, adopt NodePort Property gets exposed to the external port

kubectl expose deployment nginx-test  --type=NodePort --port 80

View all Service The state of :kubectl get services

NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.96.0.1       <none>        443/TCP        16h
nginx-test   NodePort    10.101.176.18   <none>        80:32299/TCP   77s

see Service Details of

kubectl describe services nginx-test

Access the service ：IP：32299

Name:                     nginx-test
Namespace:                default
Labels:                   app=nginx-test
Annotations:              <none>
Selector:                 app=nginx-test
Type:                     NodePort
IP Family Policy:         SingleStack
IP Families:              IPv4
IP:                       10.101.176.18
IPs:                      10.101.176.18
Port:                     <unset>  80/TCP
TargetPort:               80/TCP
NodePort:                 <unset>  32299/TCP
Endpoints:                172.17.0.3:80
Session Affinity:         None
External Traffic Policy:  Cluster
Events:                   <none>

Use of labels

By adding Label, It's easy to manage resources

see Deployment Included in Label：kubectl describe deployment

Name:                   nginx-test
Namespace:              default
CreationTimestamp:      Tue, 22 Mar 2022 09:03:09 +0800
Labels:                 app=nginx-test
Annotations:            deployment.kubernetes.io/revision: 1
Selector:               app=nginx-test
Replicas:               1 desired | 1 updated | 1 total | 1 available | 0 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge
Pod Template:
  Labels:  app=nginx-test
  Containers:
   nginx:
    Image:        nginx
    Port:         <none>
    Host Port:    <none>
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Available      True    MinimumReplicasAvailable
  Progressing    True    NewReplicaSetAvailable
OldReplicaSets:  <none>
NewReplicaSet:   nginx-test-84b478f9c5 (1/1 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  32m   deployment-controller  Scaled up replica set nginx-test-84b478f9c5 to 1

adopt Label Inquire about Pod：kubectl get pods -l app=nginx-test

NAME                          READY   STATUS    RESTARTS   AGE
nginx-test-84b478f9c5-vz7bw   1/1     Running   0          34m

adopt Label Inquire about Service：kubectl get services -l app=nginx-test

NAME         TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
nginx-test   NodePort   10.101.176.18   <none>        80:32299/TCP   16m

to Pod add to Label：kubectl label pod nginx-test-84b478f9c5-vz7bw env_role=dev

see Pod Details of ：kubectl describe pods nginx-test-84b478f9c5-vz7bw

Name:         nginx-test-84b478f9c5-vz7bw
Namespace:    default
Priority:     0
Node:         minikube/192.168.49.2
Start Time:   Tue, 22 Mar 2022 09:03:09 +0800
Labels:       app=nginx-test
              env_role=dev

adopt Label Delete service ：kubectl delete service -l app=nginx-test

service "nginx-test" deleted

kubectl get service

NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP   16h