Kubernetes集群部署(第二篇)

news/2024/7/7 9:02:20 标签: kubernetes, 容器, 云原生

安装flannel

        Master 节点NotReady 的原因就是因为没有使用任何的网络插件,此时Node 和Master的连接还不正常。目前最流行的Kubernetes 网络插件有Flannel、Calico、Canal、Weave 这里选择使用flannel。

flannel提取链接:https://pan.baidu.com/s/1fLJKhBtcONFCln6_u3xMPQ?pwd=1mf2 
提取码:1mf2

所有主机:

master上传kube-flannel.yml,所有主机上传flannel_v0.12.0-amd64.tar

 

[root@k8s-master ~]# docker load < flannel_v0.12.0-amd64.tar

256a7af3acb1: Loading layer  5.844MB/5.844MB
d572e5d9d39b: Loading layer  10.37MB/10.37MB
57c10be5852f: Loading layer  2.249MB/2.249MB
7412f8eefb77: Loading layer  35.26MB/35.26MB
05116c9ff7bf: Loading layer   5.12kB/5.12kB
Loaded image: quay.io/coreos/flannel:v0.12.0-amd64

 在所有主机上上传解压cni-plugins-linux-amd64-v0.8.6.tgz

[root@k8s-master ~]# tar xf cni-plugins-linux-amd64-v0.8.6.tgz 
[root@k8s-master ~]# cp flannel /opt/cni/bin/

master主机:

[root@k8s-master ~]#  kubectl apply -f kube-flannel.yml

podsecuritypolicy.policy/psp.flannel.unprivileged created
Warning: rbac.authorization.k8s.io/v1beta1 ClusterRole is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 ClusterRole
clusterrole.rbac.authorization.k8s.io/flannel created
Warning: rbac.authorization.k8s.io/v1beta1 ClusterRoleBinding is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 ClusterRoleBinding
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds-amd64 created
daemonset.apps/kube-flannel-ds-arm64 created
daemonset.apps/kube-flannel-ds-arm created
daemonset.apps/kube-flannel-ds-ppc64le created
daemonset.apps/kube-flannel-ds-s390x created

[root@k8s-master ~]#  kubectl get nodes

NAME         STATUS   ROLES                  AGE   VERSION
k8s-master   Ready    control-plane,master   19h   v1.20.0
k8s-node1    Ready    <none>                 19h   v1.20.0
k8s-node2    Ready    <none>                 19h   v1.20.0

[root@k8s-master ~]# kubectl get pods -n kube-system

NAME                                 READY   STATUS    RESTARTS   AGE
coredns-7f89b7bc75-bq88g             1/1     Running   0          19h
coredns-7f89b7bc75-nmmsf             1/1     Running   0          19h
etcd-k8s-master                      1/1     Running   0          19h
kube-apiserver-k8s-master            1/1     Running   0          19h
kube-controller-manager-k8s-master   1/1     Running   0          19h
kube-flannel-ds-amd64-6vh6f          1/1     Running   4          36m
kube-flannel-ds-amd64-jxgjb          1/1     Running   0          36m
kube-flannel-ds-amd64-mxrz5          1/1     Running   4          36m
kube-proxy-94cl4                     1/1     Running   0          19h
kube-proxy-ncwg6                     1/1     Running   0          19h
kube-proxy-nvnr6                     1/1     Running   0          19h
kube-scheduler-k8s-master            1/1     Running   0          19h

已经是ready状态

三、安装Dashboard UI

3.1、部署Dashboard

dashboard的github仓库地址:https://github.com/kubernetes/dashboard

代码仓库当中,有给出安装示例的相关部署文件,我们可以直接获取之后,直接部署即可

[root@k8s-master ~]# wget https://raw.githubusercontent.com/kubernetes/dashboard/master/aio/deploy/recommended.yaml

--2023-08-10 15:46:20--  https://raw.githubusercontent.com/kubernetes/dashboard/master/aio/deploy/recommended.yaml
正在解析主机 raw.githubusercontent.com (raw.githubusercontent.com)... 185.199.110.133, 185.199.111.133, 185.199.108.133, ...
正在连接 raw.githubusercontent.com (raw.githubusercontent.com)|185.199.110.133|:443... 已连接。
无法建立 SSL 连接。

         默认这个部署文件当中,会单独创建一个名为kubernetes-dashboard的命名空间,并将kubernetes-dashboard部署在该命名空间下。dashboard的镜像来自docker hub官方,所以可不用修改镜像地址,直接从官方获取即可。

3.2、开放端口设置

recommended.yaml文件提取链接:https://pan.baidu.com/s/1OYeC84YNY2_HZ1699n8Eug?pwd=7fhp 
提取码:7fhp

        在默认情况下,dashboard并不对外开放访问端口,这里简化操作,直接使用nodePort的方式将其端口暴露出来,修改serivce部分的定义:

[root@k8s-master ~]# docker pull kubernetesui/dashboard:v2.0.0

v2.0.0: Pulling from kubernetesui/dashboard
2a43ce254c7f: Pull complete 
Digest: sha256:06868692fb9a7f2ede1a06de1b7b32afabc40ec739c1181d83b5ed3eb147ec6e
Status: Downloaded newer image for kubernetesui/dashboard:v2.0.0
docker.io/kubernetesui/dashboard:v2.0.0

[root@k8s-master ~]# docker pull kubernetesui/metrics-scraper:v1.0.4

v1.0.4: Pulling from kubernetesui/metrics-scraper
07008dc53a3e: Pull complete 
1f8ea7f93b39: Pull complete 
04d0e0aeff30: Pull complete 
Digest: sha256:555981a24f184420f3be0c79d4efb6c948a85cfce84034f85a563f4151a81cbf
Status: Downloaded newer image for kubernetesui/metrics-scraper:v1.0.4
docker.io/kubernetesui/metrics-scraper:v1.0.4

[root@k8s-master ~]# vim recommended.yaml
 
 30 ---
 31 
 32 kind: Service
 33 apiVersion: v1
 34 metadata:
 35   labels:
 36     k8s-app: kubernetes-dashboard
 37   name: kubernetes-dashboard
 38   namespace: kubernetes-dashboard
 39 spec:
 40   type: NodePort
 41   ports:
 42     - port: 443
 43       targetPort: 8443
 44       nodePort: 32443
 45   selector:
 46     k8s-app: kubernetes-dashboard
 47 
 48 ---

192           image: kubernetesui/dashboard:v2.0.0
276           image: kubernetesui/metrics-scraper:v1.0.4

3.3、权限配置

配置一个超级管理员权限

[root@k8s-master ~]# vim recommended.yaml 

155 ---
156 
157 apiVersion: rbac.authorization.k8s.io/v1
158 kind: ClusterRoleBinding
159 metadata:
160   name: kubernetes-dashboard
161 roleRef:
162   apiGroup: rbac.authorization.k8s.io
163   kind: ClusterRole
164   name: cluster-admin
165 subjects:
166   - kind: ServiceAccount
167     name: kubernetes-dashboard
168     namespace: kubernetes-dashboard
169 
170 ---

[root@k8s-master ~]# kubectl apply -f recommended.yaml

namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created

[root@k8s-master ~]#  kubectl get pods -n kubernetes-dashboard

NAME                                         READY   STATUS    RESTARTS   AGE
dashboard-metrics-scraper-7b59f7d4df-fp8qx   1/1     Running   0          67s
kubernetes-dashboard-74d688b6bc-qkwrn        1/1     Running   0          67s

[root@k8s-master ~]#  kubectl get pods -A  -o wide

NAMESPACE              NAME                                         READY   STATUS    RESTARTS   AGE   IP              NODE         NOMINATED NODE   READINESS GATES
kube-system            coredns-7f89b7bc75-bq88g                     1/1     Running   0          20h   10.244.0.2      k8s-master   <none>           <none>
kube-system            coredns-7f89b7bc75-nmmsf                     1/1     Running   0          20h   10.244.0.3      k8s-master   <none>           <none>
kube-system            etcd-k8s-master                              1/1     Running   0          20h   192.168.2.116   k8s-master   <none>           <none>
kube-system            kube-apiserver-k8s-master                    1/1     Running   0          20h   192.168.2.116   k8s-master   <none>           <none>
kube-system            kube-controller-manager-k8s-master           1/1     Running   0          20h   192.168.2.116   k8s-master   <none>           <none>
kube-system            kube-flannel-ds-amd64-6vh6f                  1/1     Running   4          58m   192.168.2.117   k8s-node1    <none>           <none>
kube-system            kube-flannel-ds-amd64-jxgjb                  1/1     Running   0          58m   192.168.2.116   k8s-master   <none>           <none>
kube-system            kube-flannel-ds-amd64-mxrz5                  1/1     Running   4          58m   192.168.2.118   k8s-node2    <none>           <none>
kube-system            kube-proxy-94cl4                             1/1     Running   0          19h   192.168.2.117   k8s-node1    <none>           <none>
kube-system            kube-proxy-ncwg6                             1/1     Running   0          20h   192.168.2.116   k8s-master   <none>           <none>
kube-system            kube-proxy-nvnr6                             1/1     Running   0          19h   192.168.2.118   k8s-node2    <none>           <none>
kube-system            kube-scheduler-k8s-master                    1/1     Running   0          20h   192.168.2.116   k8s-master   <none>           <none>
kubernetes-dashboard   dashboard-metrics-scraper-7b59f7d4df-fp8qx   1/1     Running   0          77s   10.244.2.2      k8s-node2    <none>           <none>
kubernetes-dashboard   kubernetes-dashboard-74d688b6bc-qkwrn        1/1     Running   0          77s   10.244.1.2      k8s-node1    <none>           <none>

3.4、访问Token配置

使用谷歌浏览器测试访问 https://192.168.2.116:32443

 

 

         可以看到出现如上图画面,需要我们输入一个kubeconfig文件或者一个token。事实上在安装dashboard时,也为我们默认创建好了一个serviceaccount,为kubernetes-dashboard,并为其生成好了token,我们可以通过如下指令获取该sa的token:

[root@k8s-master ~]# kubectl describe secret -n kubernetes-dashboard $(kubectl get secret -n kubernetes-dashboard |grep kubernetes-dashboard-token | awk '{print $1}') |grep token | awk '{print $2}'

kubernetes-dashboard-token-tnv6k
kubernetes.io/service-account-token
eyJhbGciOiJSUzI1NiIsImtpZCI6InB0RVQwT3JvN3AxTXNhZnFmRTduNng3NGgzcEgtN0dpU1Y3QkNnVmlET2cifQ.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.PQ_0QNs19ei_WlGK73NWJwG1YamGEQz3Gez6BlwAX4uiH_ZrVVS0G4ReWRQCLfqwFQmWlaNhuFIggfJAldxDzQ9aUtKrxbGcgdl4PQ28sT-0FpZSAS8qYtZOcM_Dv96Gp39Erm-PcPMk3vZD_TBn118l9-eAkEfgohUMBVD4cUMgL1olwgZHnlFbtrvpf_gwzF-oeGuRp8VeMXOYtB7J5_D8RSaoLpGQ-rfRq9mG0TqJ5laF_8Sb6WFsnjSb8i0_WXZ1pnXEh3_UiEgd78KlSH6wNoi4jB5B1k61KZlQ0ol9owDUDAAS-qznG8ER41KvMGs6CWt5queOjyQCK3XwQA

 

 

 

 

 

 

 

四、安装metrics-server

4.1、在Node节点上下载镜像

heapster已经被metrics-server取代

[root@k8s-node1 ~]#  docker pull bluersw/metrics-server-amd64:v0.3.6

v0.3.6: Pulling from bluersw/metrics-server-amd64
e8d8785a314f: Pull complete 
b2f4b24bed0d: Pull complete 
Digest: sha256:c9c4e95068b51d6b33a9dccc61875df07dc650abbf4ac1a19d58b4628f89288b
Status: Downloaded newer image for bluersw/metrics-server-amd64:v0.3.6
docker.io/bluersw/metrics-server-amd64:v0.3.6

[root@k8s-node1 ~]# docker tag bluersw/metrics-server-amd64:v0.3.6 k8s.gcr.io/metrics-server-amd64:v0.3.6 

4.2、修改 Kubernetes apiserver 启动参数

在kube-apiserver项中添加如下配置选项 修改后apiserver会自动重启

[root@k8s-master ~]# vim /etc/kubernetes/manifests/kube-apiserver.yaml	
 44     - --enable-aggregator-routing=true

4.3、Master上进行部署

[root@k8s-master ~]# wget https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.3.6/components.yaml

--2023-08-10 16:43:31--  https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.3.6/components.yaml
正在解析主机 github.com (github.com)... 20.205.243.166
正在连接 github.com (github.com)|20.205.243.166|:443... 已连接。
无法建立 SSL 连接。

修改安装脚本:

components.yaml文件提取链接:https://pan.baidu.com/s/1REsXCZIoy4rak3mFQDOgBg?pwd=m6xz 
提取码:m6xz

[root@k8s-master ~]# vim components.yaml

 73   template:
 74     metadata:
 75       name: metrics-server
 76       labels:
 77         k8s-app: metrics-server
 78     spec:
 79       serviceAccountName: metrics-server
 80       volumes:
 81       # mount in tmp so we can safely use from-scratch images and/or read-only containers
 82       - name: tmp-dir
 83         emptyDir: {}
 84       containers:
 85       - name: metrics-server
 86         image: k8s.gcr.io/metrics-server-amd64:v0.3.6
 87         imagePullPolicy: IfNotPresent
 88         args:
 89           - --cert-dir=/tmp
 90           - --secure-port=4443
 91           - --kubelet-preferred-address-types=InternalIP
 92           - --kubelet-insecure-tls

[root@k8s-master ~]#  kubectl create -f components.yaml

clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
Warning: apiregistration.k8s.io/v1beta1 APIService is deprecated in v1.19+, unavailable in v1.22+; use apiregistration.k8s.io/v1 APIService
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created
serviceaccount/metrics-server created
deployment.apps/metrics-server created
service/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created

等待1-2分钟后查看结果

[root@k8s-master ~]# kubectl top nodes

NAME         CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%   
k8s-master   102m         5%     1432Mi          39%       
k8s-node1    34m          1%     978Mi           26%       
k8s-node2    32m          1%     900Mi           24%       

再回到dashboard界面可以看到CPU和内存使用情况了

 到此K8S集群安装全部完成

五、应用部署测试

下面我们部署一个简单的Nginx WEB服务,该容器运行时会监听80端口。

Kubernetes 支持两种方式创建资源:

(1)用kubectl命令直接创建,在命令行中通过参数指定资源的属性。此方式简单直观,比较适合临时测试或实验使用。

[root@k8s-master ~]# kubectl run web --image=nginx --replicas=2

 (2)通过配置文件和kubectl create/apply创建。在配置文件中描述了应用的信息和需要达到的预期状态。

nginx-deployment.yaml文件提取链接:https://pan.baidu.com/s/1ZRnXausXPPr84k1sbvp2ww?pwd=4e8o 
提取码:4e8o

[root@k8s-master ~]# kubectl create -f nginx-deployment.yaml

以Deployment YAML方式创建Nginx服务

创建deployment

[root@k8s-master ~]# cat nginx-deployment.yaml 

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: 3
  selector: 
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.19.4
        ports:
        - containerPort: 80

deployment配置文件说明:

apiVersion: apps/v1	#apiVersion是当前配置格式的版本
kind: Deployment	#kind是要创建的资源类型,这里是Deploymnet
metadata:			#metadata是该资源的元数据,name是必须的元数据项
  name: nginx-deployment
  labels:
    app: nginx
spec:				#spec部分是该Deployment的规则说明
  replicas: 3		#relicas指定副本数量,默认为1
  selector: 
    matchLabels:
      app: nginx
  template:			#template定义Pod的模板,这是配置的重要部分
    metadata:		#metadata定义Pod的元数据,至少要顶一个label,label的key和value可以任意指定
      labels:
        app: nginx
    spec:			#spec描述的是Pod的规则,此部分定义pod中每一个容器的属性,name和image是必需的
      containers:
      - name: nginx
        image: nginx:1.19.4
        ports:
        - containerPort: 80

创建nginx-deployment应用

[root@k8s-master ~]# kubectl create -f nginx-deployment.yaml
deployment.apps/nginx-deployment created

查看deployment详情

[root@k8s-master ~]# kubectl get deployment

NAME               READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3/3     3            3           5m57s

查看pod在状态,正在创建中,此时应该正在拉取镜像

[root@k8s-master ~]# kubectl get pod
NAME                               READY   STATUS    RESTARTS   AGE
nginx-deployment-7947dc656-ccts9   1/1     Running   0          6m32s
nginx-deployment-7947dc656-gcwvq   1/1     Running   0          6m32s
nginx-deployment-7947dc656-kvv6t   1/1     Running   0          6m32s
web                                1/1     Running   0          73m

查看具体某个pod的状态信息

[root@k8s-master ~]# kubectl describe pod nginx-deployment-7947dc656-ccts9
Name:         nginx-deployment-7947dc656-ccts9
Namespace:    default
Priority:     0
Node:         k8s-node2/192.168.2.118
Start Time:   Thu, 10 Aug 2023 18:02:46 +0800
Labels:       app=nginx
              pod-template-hash=7947dc656
Annotations:  <none>
Status:       Running
IP:           10.244.2.4
IPs:
  IP:           10.244.2.4
Controlled By:  ReplicaSet/nginx-deployment-7947dc656
Containers:
  nginx:
    Container ID:   docker://7043ecf3c52d43fe4bc11f27b0c614aadd10534c565bd320be87fd8feac90647
    Image:          nginx:1.19.4
    Image ID:       docker-pullable://nginx@sha256:c3a1592d2b6d275bef4087573355827b200b00ffc2d9849890a4f3aa2128c4ae
    Port:           80/TCP
    Host Port:      0/TCP
    State:          Running
      Started:      Thu, 10 Aug 2023 18:07:49 +0800
    Ready:          True
    Restart Count:  0
    Environment:    <none>
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-s7c9z (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             True 
  ContainersReady   True 
  PodScheduled      True 
Volumes:
  default-token-s7c9z:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-s7c9z
    Optional:    false
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  7m43s  default-scheduler  Successfully assigned default/nginx-deployment-7947dc656-ccts9 to k8s-node2
  Normal  Pulling    7m42s  kubelet            Pulling image "nginx:1.19.4"
  Normal  Pulled     2m41s  kubelet            Successfully pulled image "nginx:1.19.4" in 5m1.644567511s
  Normal  Created    2m41s  kubelet            Created container nginx
  Normal  Started    2m40s  kubelet            Started container nginx

[root@k8s-master ~]# kubectl get pod -o wide        #创建成功,状态为Running

NAME                               READY   STATUS    RESTARTS   AGE    IP           NODE        NOMINATED NODE   READINESS GATES
nginx-deployment-7947dc656-ccts9   1/1     Running   0          9m3s   10.244.2.4   k8s-node2   <none>           <none>
nginx-deployment-7947dc656-gcwvq   1/1     Running   0          9m3s   10.244.1.4   k8s-node1   <none>           <none>
nginx-deployment-7947dc656-kvv6t   1/1     Running   0          9m3s   10.244.2.5   k8s-node2   <none>           <none>
web                                1/1     Running   0          75m    10.244.2.3   k8s-node2   <none>           <none>

        如果要删除这些资源,执行 kubectl delete deployment nginx-deployment 或者 kubectl delete -f nginx-deployment.yaml。

测试Pod访问

[root@k8s-master ~]# curl --head http://10.244.2.3

HTTP/1.1 200 OK
Server: nginx/1.21.5
Date: Thu, 10 Aug 2023 10:12:48 GMT
Content-Type: text/html
Content-Length: 615
Last-Modified: Tue, 28 Dec 2021 15:28:38 GMT
Connection: keep-alive
ETag: "61cb2d26-267"
Accept-Ranges: bytes


[root@k8s-master ~]# elinks --dump http://10.244.2.3
                               Welcome to nginx!

   If you see this page, the nginx web server is successfully installed and
   working. Further configuration is required.

   For online documentation and support please refer to [1]nginx.org.
   Commercial support is available at [2]nginx.com.

   Thank you for using nginx.

References

   Visible links
   1. http://nginx.org/
   2. http://nginx.com/

 


http://www.niftyadmin.cn/n/4927591.html

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