K8S 集群部署

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目录大纲：

0x01：安装环境介绍

0x02：k8s 集群安装

0x03：k8s 常见命令

**0x01：安装环境介绍**

三台虚机搭建，配置如下：

<table><tbody><tr><td width="94" valign="top"><section>节点类型<br></section></td><td width="94" valign="top"><section>节点名称<br></section></td><td width="155" valign="top"><section>节点 IP<br></section></td><td width="69" valign="top"><section>CPU 配置<br></section></td><td width="58" valign="top"><section>内存<br></section></td></tr><tr><td width="94" valign="top"><section>Master 节点<br></section></td><td width="94" valign="top"><section>k8s-master</section></td><td width="155" valign="top"><section>192.168.220.200</section></td><td width="69" valign="top"><section>2 核<br></section></td><td width="58" valign="top"><section>4G<br></section></td></tr><tr><td width="94" valign="top"><section>Node 节点<br></section></td><td width="94" valign="top"><section>k8s-node1</section></td><td width="155" valign="top"><section>192.168.220.201</section></td><td width="69" valign="top"><section>2 核</section></td><td width="58" valign="top"><section>2G<br></section></td></tr><tr><td width="94" valign="top"><section>Node 节点</section></td><td width="94" valign="top"><section>k8s-node2</section></td><td width="155" valign="top"><section>192.168.220.202</section></td><td width="69" valign="top"><section>2 核</section></td><td width="58" valign="top"><section>2G<br></section></td></tr></tbody></table>

docker 版本：Docker version 20.10.7

k8s 版本：1.20.9

**0x02：k8s 集群安装**

![](http://kmgy.top:9000/image/2022/10/31/202210311441751.png)

安装集群：

这里把前前后后所有的步骤都列出来，方便各位实验！

## 一、容器运行环境安装 --docker 安装

### 1、移除旧版本 docker 相关包

```
sudo yum remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine

```

### 2、配置 yum 源

```
yum install -y yum-utils
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

```

### 3、安装 docker

```
yum install -y docker-ce-20.10.7 docker-ce-cli-20.10.7  containerd.io-1.4.6

```

### 4、启动 docker

```
systemctl enable docker --now

```

### 5、配置加速

```
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://uoriix0a.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

```

查看下三台机器 docker 状态：

![](http://kmgy.top:9000/image/2022/10/31/202210311441513.png)

## 二、k8s 集群安装

上面第一步已经给三台机器都安装了容器运行环境 --Docker，接下来开始安装 k8s 集群。

### 1、预备环境 -- 基础环境配置

所有机器执行以下操作：

*   各个机器设置自己的域名，不能重复
    
*   将 SELinux 设置为 permissive 模式
    
*   关闭 swap
    
*   允许 iptables 检查桥接流量

```
#各个机器设置自己的域名
hostnamectl set-hostname xxxx
# 将 SELinux 设置为 permissive 模式（相当于将其禁用）
sudo setenforce 0
sudo sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
#关闭swap
swapoff -a  
sed -ri 's/.*swap.*/#&/' /etc/fstab
#允许 iptables 检查桥接流量
cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf
br_netfilter
EOF
cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system

```

![](http://kmgy.top:9000/image/2022/10/31/202210311441468.png)

### 2、安装三大件 --kubelet、kubeadm、kubectl

```
cat <<EOF | sudo tee /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
   http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
exclude=kubelet kubeadm kubectl
EOF
# 安装k8s三大件
sudo yum install -y kubelet-1.20.9 kubeadm-1.20.9 kubectl-1.20.9 --disableexcludes=kubernetes
# 三台机器都启动kubelet，也就是厂长
sudo systemctl enable --now kubelet

```

### 3、使用 kubeadm 引导集群

#### 3.1、下载各个机器所需的镜像

```
sudo tee ./images.sh <<-'EOF'
#!/bin/bash
images=(
kube-apiserver:v1.20.9
kube-proxy:v1.20.9
kube-controller-manager:v1.20.9
kube-scheduler:v1.20.9
coredns:1.7.0
etcd:3.4.13-0
pause:3.2
)
for imageName in ${images[@]} ; do
docker pull registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images/$imageName
done
EOF
chmod +x ./images.sh && ./images.sh

```

#### 3.2、初始化主节点

使用 Kubeadm 将节点变为 Master 节点。

```
#所有机器添加master域名映射，以下需要修改为自己的
echo "192.168.220.200  cluster-endpoint" >> /etc/hosts
#主节点初始化，只在主节点执行
kubeadm init \
--apiserver-advertise-address=172.31.106.101 \
--control-plane-endpoint=cluster-endpoint \
--image-repository registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images \
--kubernetes-version v1.20.9 \
--service-cidr=10.96.0.0/16 \
--pod-network-cidr=172.20.0.0/16
#所有网络范围不重叠

```

这里需要注意其中的所有 IP 网段不重叠。出现如下返回表示 Master 节点初始化成功，并且告诉你还有一些配置需要执行。

```
Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

Alternatively, if you are the root user, you can run:

export KUBECONFIG=/etc/kubernetes/admin.conf

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

You can now join any number of control-plane nodes by copying certificate authorities
and service account keys on each node and then running the following as root:

kubeadm join cluster-endpoint:6443 --token ltgtar.hgy7iryz07cyrpah \
    --discovery-token-ca-cert-hash sha256:d8ca9e66af720d199f4d398cf63e43d8cae82590c4abe689cb95077b3370bf05 \
    --control-plane

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join cluster-endpoint:6443 --token ltgtar.hgy7iryz07cyrpah --discovery-token-ca-cert-hash sha256:d8ca9e66af720d199f4d398cf63e43d8cae82590c4abe689cb95077b3370bf05

```

从上面初始化主节点的执行返回，提示可以加入任意多的主节点，也可以加入任意多的工作节点。

#### 3.3、安装网络插件

```
curl https://docs.projectcalico.org/archive/v3.20/manifests/calico.yaml -O
kubectl apply -f calico.yaml

```

下载完 calico.yaml 后，需要注意修改其中：

```
3888行             - name: CALICO_IPV4POOL_CIDR
3889行               value: "172.20.0.0/16"  //这里改成前面初始化是填的pod网络地址

```

![](http://kmgy.top:9000/image/2022/10/31/202210311441578.png)

如上图可以看到 calico 安装成功，使用命令：kubectl get pod -A | grep calico

**遇到问题：The connection to the server localhost:8080 was refused - did you specify the right host or port?**

具体根据情况，此处记录linux设置该环境变量

- **方式一：编辑文件设置**
  	   **vim /etc/profile**
        	   **在底部增加新的环境变量 export KUBECONFIG=/etc/kubernetes/admin.conf**

- **方式二:直接追加文件内容**
  	**echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> /etc/profile**

**source /etc/profile**

#### 3.4、加入 node 节点

```
kubeadm join cluster-endpoint:6443 --token ltgtar.hgy7iryz07cyrpah --discovery-token-ca-cert-hash sha256:d8ca9e66af720d199f4d398cf63e43d8cae82590c4abe689cb95077b3370bf05

```

上面命令 24h 有效，如果令牌丢失，可以重新生成新令牌：

```
kubeadm token create --print-join-command

```

将其他两台都加入集群即可。

### 4、验证集群状态

```
kubectl get nodes
```

![](http://kmgy.top:9000/image/2022/10/31/202210311441615.png)

## 三、部署可视化界面 --dashboard

### 1、部署 dashboard

```
# Copyright 2017 The Kubernetes Authors.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#     http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

apiVersion: v1
kind: Namespace
metadata:
  name: kubernetes-dashboard

---

apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard

---

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-certs
  namespace: kubernetes-dashboard
type: Opaque

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-csrf
  namespace: kubernetes-dashboard
type: Opaque
data:
  csrf: ""

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-key-holder
  namespace: kubernetes-dashboard
type: Opaque

---

kind: ConfigMap
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-settings
  namespace: kubernetes-dashboard

---

kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
rules:

# Allow Dashboard to get, update and delete Dashboard exclusive secrets.

- apiGroups: [""]
    resources: ["secrets"]
    resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs", "kubernetes-dashboard-csrf"]
    verbs: ["get", "update", "delete"]

# Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.

- apiGroups: [""]
    resources: ["configmaps"]
    resourceNames: ["kubernetes-dashboard-settings"]
    verbs: ["get", "update"]

# Allow Dashboard to get metrics.

- apiGroups: [""]
    resources: ["services"]
    resourceNames: ["heapster", "dashboard-metrics-scraper"]
    verbs: ["proxy"]

- apiGroups: [""]
    resources: ["services/proxy"]
    resourceNames: ["heapster", "http:heapster:", "https:heapster:", "dashboard-metrics-scraper", "http:dashboard-metrics-scraper"]
    verbs: ["get"]

---

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
rules:

# Allow Metrics Scraper to get metrics from the Metrics server

- apiGroups: ["metrics.k8s.io"]
    resources: ["pods", "nodes"]
    verbs: ["get", "list", "watch"]

---

apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: kubernetes-dashboard
subjects:

- kind: ServiceAccount
    name: kubernetes-dashboard
    namespace: kubernetes-dashboard

---

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: kubernetes-dashboard
subjects:

- kind: ServiceAccount
    name: kubernetes-dashboard
    namespace: kubernetes-dashboard

---

kind: Deployment
apiVersion: apps/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kubernetes-dashboard
  template:
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
    spec:
      containers:
        - name: kubernetes-dashboard
          image: kubernetesui/dashboard:v2.3.1
          imagePullPolicy: Always
          ports:
            - containerPort: 8443
              protocol: TCP
          args:
            - --auto-generate-certificates
            - --namespace=kubernetes-dashboard
            # Uncomment the following line to manually specify Kubernetes API server Host
            # If not specified, Dashboard will attempt to auto discover the API server and connect
            # to it. Uncomment only if the default does not work.
            # - --apiserver-host=http://my-address:port
          volumeMounts:
            - name: kubernetes-dashboard-certs
              mountPath: /certs
              # Create on-disk volume to store exec logs
            - mountPath: /tmp
              name: tmp-volume
          livenessProbe:
            httpGet:
              scheme: HTTPS
              path: /
              port: 8443
            initialDelaySeconds: 30
            timeoutSeconds: 30
          securityContext:
            allowPrivilegeEscalation: false
            readOnlyRootFilesystem: true
            runAsUser: 1001
            runAsGroup: 2001
      volumes:
        - name: kubernetes-dashboard-certs
          secret:
            secretName: kubernetes-dashboard-certs
        - name: tmp-volume
          emptyDir: {}
      serviceAccountName: kubernetes-dashboard
      nodeSelector:
        "kubernetes.io/os": linux
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule

---

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: dashboard-metrics-scraper
  name: dashboard-metrics-scraper
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 8000
      targetPort: 8000
  selector:
    k8s-app: dashboard-metrics-scraper

---

kind: Deployment
apiVersion: apps/v1
metadata:
  labels:
    k8s-app: dashboard-metrics-scraper
  name: dashboard-metrics-scraper
  namespace: kubernetes-dashboard
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: dashboard-metrics-scraper
  template:
    metadata:
      labels:
        k8s-app: dashboard-metrics-scraper
      annotations:
        seccomp.security.alpha.kubernetes.io/pod: 'runtime/default'
    spec:
      containers:
        - name: dashboard-metrics-scraper
          image: kubernetesui/metrics-scraper:v1.0.6
          ports:
            - containerPort: 8000
              protocol: TCP
          livenessProbe:
            httpGet:
              scheme: HTTP
              path: /
              port: 8000
            initialDelaySeconds: 30
            timeoutSeconds: 30
          volumeMounts:
          - mountPath: /tmp
            name: tmp-volume
          securityContext:
            allowPrivilegeEscalation: false
            readOnlyRootFilesystem: true
            runAsUser: 1001
            runAsGroup: 2001
      serviceAccountName: kubernetes-dashboard
      nodeSelector:
        "kubernetes.io/os": linux
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule
      volumes:
        - name: tmp-volume
          emptyDir: {}
```

```
kubernetes官方提供的可视化界面
https://github.com/kubernetes/dashboard
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.3.1/aio/deploy/recommended.yaml

```

这里说一下，k8s 安装资源可以通过 yaml 配置文件来安装，安装命令是：kubectl apply -f xx.yaml

### 2、设置访问端口

```
kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard
iptables -I INPUT -p tcp --dport 32062 -j ACCEPT
```

将 type: ClusterIP 改为 type: NodePort

```
kubectl get svc -A | grep dashboard
```

![](http://kmgy.top:9000/image/2022/10/31/202210311441558.png)

因为是 NodePort 的网络模式，所以可以通过这样访问：

https:// 集群任意节点 IP: 端口  也就是：https://192.168.220.200:32062

![](http://kmgy.top:9000/image/2022/10/31/202210311442934.png)

### 3、创建访问账号

```
#创建访问账号，准备一个yaml文件；vi dash.yamlapiVersion: v1kind: ServiceAccountmetadata:  name: admin-user  namespace: kubernetes-dashboard---apiVersion: rbac.authorization.k8s.io/v1kind: ClusterRoleBindingmetadata:  name: admin-userroleRef:  apiGroup: rbac.authorization.k8s.io  kind: ClusterRole  name: cluster-adminsubjects:- kind: ServiceAccount  name: admin-user  namespace: kubernetes-dashboard

```

执行：

```
kubectl apply -f dash.yaml

```

### 4、令牌访问

```
#获取访问令牌
kubectl -n kubernetes-dashboard get secret $(kubectl -n kubernetes-dashboard get sa/admin-user -o jsonpath="{.secrets[0].name}") -o go-template="{{.data.token | base64decode}}"
# 生成的令牌
eyJhbGciOiJSUzI1NiIsImtpZCI6IjlfVExfa19VaDBkVGp4cTZUVFdZbl95T29faVpqZ0NWM2EtOXhPeVRGMHMifQ.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.iomC1bOphyxKTuEI3cioT1_17P-rvw6UgVtuK-cEdcU8dZ1n50hOEOUnUx9qi8Hp9X03OeksB4hDMei6smXvEPRs-EkE0wN0XUF9JKdtXsfWYu0NI5WdvuV2Cr7TAXx2ALd8kwLfXqjKBaFS0-i5O7Tg0PhiUwtmLfYHVal5OznZTIIGCnMsRE3io46BmfbfvwStlhcibidEpRG8zBnY_iM12rdlnQHYhfC4f4emzoh6BH5sz7xnKrYC9a__N6bClEOmJeYjsrW2jMFy90IaMLukXHjDJsqwVTVB_thKVoVqhgv02o8yI8t0teSTdnJd1JRKiNFUCbd0LXyei7Qz0g

```

![](http://kmgy.top:9000/image/2022/10/31/202210311442988.png)

### 5、界面

使用上面生成的令牌登录 k8s-dashboard 界面：

![](http://kmgy.top:9000/image/2022/10/31/202210311442115.png)

可以查看集群的 pod 状态：

![](http://kmgy.top:9000/image/2022/10/31/202210311442225.png)

可以进入某个 pod

![](http://kmgy.top:9000/image/2022/10/31/202210311442314.png)

![](http://kmgy.top:9000/image/2022/10/31/202210311442299.png)

**0x03：k8s 常见命令**

获取 node 节点状态：kubectl get node

![](http://kmgy.top:9000/image/2022/10/31/202210311442564.png)

获取 pod 状态：kubectl get pod 相当于 kubectl get pod -n default，表示查看 namespace=default 下的 pod 资源

![](http://kmgy.top:9000/image/2022/10/31/202210311442969.png)

查看所有 namespace 的 pod 资源：kubectl get pod -A

![](http://kmgy.top:9000/image/2022/10/31/202210311442171.png)

根据 yaml 配置文件创建资源：kubectl apply -f xxx.yaml

通过 yaml 配置文件可以创建各类资源，如 pod、service、namespace 等。

删除 pod：kubectl delete podpod 名称

查看 pod 的日志：kubectl logs mynginx

![](http://kmgy.top:9000/image/2022/10/31/202210311442383.png)

查看 pod 的详细信息：kubectl describe pod mynginx

```
[root@k8s-master ~]# kubectl describe pod mynginx
Name:         mynginx
Namespace:    default
Priority:     0
Node:         k8s-node2/192.168.220.202
Start Time:   Fri, 05 Aug 2022 16:01:14 +0800
Labels:       run=mynginx
Annotations:  cni.projectcalico.org/containerID: 9f1252d8956e5085b3f5ce39bdb1ad7711c703ece37685d0776ea07797af378f
              cni.projectcalico.org/podIP: 172.20.169.135/32
              cni.projectcalico.org/podIPs: 172.20.169.135/32
Status:       Running
IP:           172.20.169.135
IPs:
  IP:  172.20.169.135
Containers:
  mynginx:
    Container ID:   docker://5eab654bdff8ccaf61c7413c349b4aa9be1d09fc7bc6a3566d4d9743ff8dd2c1
    Image:          nginx
    Image ID:       docker-pullable://nginx@sha256:0d17b565c37bcbd895e9d92315a05c1c3c9a29f762b011a10c54a66cd53c9b31
    Port:           <none>
    Host Port:      <none>
    State:          Running
      Started:      Wed, 10 Aug 2022 13:08:45 +0800
    Last State:     Terminated
      Reason:       Completed
      Exit Code:    0
      Started:      Tue, 09 Aug 2022 15:17:33 +0800
      Finished:     Tue, 09 Aug 2022 18:59:44 +0800
    Ready:          True
    Restart Count:  2
    Environment:    <none>
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-gqk59 (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             True 
  ContainersReady   True 
  PodScheduled      True 
Volumes:
  default-token-gqk59:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-gqk59
    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
  ----     ------          ----               ----     -------
  Warning  FailedMount     13m                kubelet  MountVolume.SetUp failed for volume "default-token-gqk59" : failed to sync secret cache: timed out waiting for the condition
  Normal   SandboxChanged  12m (x2 over 13m)  kubelet  Pod sandbox changed, it will be killed and re-created.
  Normal   Pulling         12m                kubelet  Pulling image "nginx"
  Normal   Pulled          12m                kubelet  Successfully pulled image "nginx" in 15.316422653s
  Normal   Created         12m                kubelet  Created container mynginx
  Normal   Started         12m                kubelet  Started container mynginx

```

k8s 的命令还有很多，后面会再通过其他篇幅介绍。