虚拟机k8s搭建

1.永久关闭swap,命令行键入以下指令

systemctl stop firewalld
systemctl disable firewalld
setenforce 0
sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
swapoff -a
sed -i 's/.*swap.*/#&/' /etc/fstab

2.修改网络配置，命令行键入以下指令

cat <<EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF

sysctl -p /etc/sysctl.d/k8s.conf

2.1错误 : cannot stat /proc/sys/net/bridge/bridge-nf-call-ip6tables: 没有那个文件或目录...

# 临时解决，重启失效
modprobe br_netfilter

# 为了开机加载上面这个模块
cat > /etc/rc.sysinit << EOF
#!/bin/bash
for file in /etc/sysconfig/modules/*.modules ; do
[ -x $file ] && $file
done
EOF
cat > /etc/sysconfig/modules/br_netfilter.modules << EOF
modprobe br_netfilter
EOF
chmod 755 /etc/sysconfig/modules/br_netfilter.modules
lsmod |grep br_netfilter

3.安装docker ，k8s运行依赖docker

# step 1: 安装必要的一些系统工具
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# Step 2: 添加软件源信息
sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# Step 3: 更新并安装Docker-CE
sudo yum makecache fast
# 注意：
# 官方软件源默认启用了最新的软件，您可以通过编辑软件源的方式获取各个版本的软件包。例如官方并没有将测试版本的软件源置为可用，您可以通过以下方式开启。同理可以开启各种测试版本等。
# vim /etc/yum.repos.d/docker-ee.repo
#   将[docker-ce-test]下方的enabled=0修改为enabled=1
# Step 4: 查找Docker-CE的版本:
yum list docker-ce.x86_64 --showduplicates | sort -r
#   Loading mirror speeds from cached hostfile
#   Loaded plugins: branch, fastestmirror, langpacks
#   docker-ce.x86_64            17.03.1.ce-1.el7.centos            docker-ce-stable
#   docker-ce.x86_64            17.03.1.ce-1.el7.centos            @docker-ce-stable
#   docker-ce.x86_64            17.03.0.ce-1.el7.centos            docker-ce-stable
#   Available Packages
# Step5: 安装指定版本的Docker-CE: (VERSION例如上面的17.03.0.ce.1-1.el7.centos)
# sudo yum -y install docker-ce-[VERSION]
sudo yum -y install docker-ce-18.06.0.ce-3.el7
# Step 6: 开启Docker服务
sudo service docker start
# Step 7: 开机启动
sudo systemctl enable docker
# Step 8: 查看状态
sudo systemctl status docker

3.1 docker加速

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
#  xxxxxx换成自己的连接, 阿里云镜像容器服务可以找到(镜像加速)
{
     "registry-mirrors": [
        "https://xxxxxx.mirror.aliyuncs.com",
        "http://hub-mirror.c.163.com",
        "https://docker.mirrors.ustc.edu.cn",
        "https://registry.docker-cn.com",
        "https://ung2thfc.mirror.aliyuncs.com"
        ] 
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

4. 配置kubernets国内源

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

5. 从kubeernets源下载kubeadm kubelet kubectl

 # 指定版本，不推荐使用最新版
yum install -y kubelet-1.20.5 kubeadm-1.20.5 kubectl-1.20.5 --disableexcludes=kubernetes 
systemctl enable kubelet.service

5.1.1 修改kubelet配置

vim /etc/sysconfig/kubelet

KUBELET_EXTRA_ARGS="--fail-swap-on=false"

完成以上可进行虚拟机克隆，以下步骤node节点不需要执行，无node节点也可

5.1.2 使用阿里云镜像初始化

运行kubeadm init时加上阿里云镜像的参数--image-repository=registry.aliyuncs.com/google_containers，如下：

kubeadm init --image-repository=registry.aliyuncs.com/google_containers --pod-network-cidr=10.244.0.0/16 --kubernetes-version=v1.20.5 --v=6

6. 创建文件夹 拷贝配置信息（根据提示操作）

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 &quot;kubectl apply -f [podnetwork].yaml&quot; with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

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

kubeadm join 192.168.1.13:6443 --token su0cm4.0fgt1nuyq61yvknu \
    --discovery-token-ca-cert-hash sha256:38dee19cd610ff56071e95399880cb68765674f85f83a13338870dc7d347da8c

7. 安装fannel，coredns组件需要，域名解析使用

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

7.1如果网络不通，无法下载也可以直接复制下面的yaml去直接创建，此版本与kubectl v1.20.5对应

---
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
  name: psp.flannel.unprivileged
  annotations:
    seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/default
    seccomp.security.alpha.kubernetes.io/defaultProfileName: docker/default
    apparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/default
    apparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default
spec:
  privileged: false
  volumes:
  - configMap
  - secret
  - emptyDir
  - hostPath
  allowedHostPaths:
  - pathPrefix: "/etc/cni/net.d"
  - pathPrefix: "/etc/kube-flannel"
  - pathPrefix: "/run/flannel"
  readOnlyRootFilesystem: false
  # Users and groups
  runAsUser:
    rule: RunAsAny
  supplementalGroups:
    rule: RunAsAny
  fsGroup:
    rule: RunAsAny
  # Privilege Escalation
  allowPrivilegeEscalation: false
  defaultAllowPrivilegeEscalation: false
  # Capabilities
  allowedCapabilities: ['NET_ADMIN', 'NET_RAW']
  defaultAddCapabilities: []
  requiredDropCapabilities: []
  # Host namespaces
  hostPID: false
  hostIPC: false
  hostNetwork: true
  hostPorts:
  - min: 0
    max: 65535
  # SELinux
  seLinux:
    # SELinux is unused in CaaSP
    rule: 'RunAsAny'
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
rules:
- apiGroups: ['extensions']
  resources: ['podsecuritypolicies']
  verbs: ['use']
  resourceNames: ['psp.flannel.unprivileged']
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: flannel
subjects:
- kind: ServiceAccount
  name: flannel
  namespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: flannel
  namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-system
  labels:
    tier: node
    app: flannel
data:
  cni-conf.json: |
    {
      "name": "cbr0",
      "cniVersion": "0.3.1",
      "plugins": [
        {
          "type": "flannel",
          "delegate": {
            "hairpinMode": true,
            "isDefaultGateway": true
          }
        },
        {
          "type": "portmap",
          "capabilities": {
            "portMappings": true
          }
        }
      ]
    }
  net-conf.json: |
    {
      "Network": "10.244.0.0/16",
      "Backend": {
        "Type": "vxlan"
      }
    }
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-system
  labels:
    tier: node
    app: flannel
spec:
  selector:
    matchLabels:
      app: flannel
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: kubernetes.io/os
                operator: In
                values:
                - linux
      hostNetwork: true
      priorityClassName: system-node-critical
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: quay.io/coreos/flannel:v0.13.1-rc2
        command:
        - cp
        args:
        - -f
        - /etc/kube-flannel/cni-conf.json
        - /etc/cni/net.d/10-flannel.conflist
        volumeMounts:
        - name: cni
          mountPath: /etc/cni/net.d
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      containers:
      - name: kube-flannel
        image: quay.io/coreos/flannel:v0.13.1-rc2
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr
        resources:
          requests:
            cpu: "100m"
            memory: "50Mi"
          limits:
            cpu: "100m"
            memory: "50Mi"
        securityContext:
          privileged: false
          capabilities:
            add: ["NET_ADMIN", "NET_RAW"]
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        volumeMounts:
        - name: run
          mountPath: /run/flannel
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      volumes:
      - name: run
        hostPath:
          path: /run/flannel
      - name: cni
        hostPath:
          path: /etc/cni/net.d
      - name: flannel-cfg
        configMap:
          name: kube-flannel-cfg

8. 查看安装情况

kubectl get pods -n kube-system

9. 开启主节点可以负载，默认情况是不会负载到主节点

# 查看hostname
hostname
# 开启主节点负载
kubectl taint node [主节点的hostname] node-role.kubernetes.io/master-

10. 部署可视化插件

sudo docker run -d \
  --restart=unless-stopped \
  --name=kuboard \
  -p 9999:80/tcp \
  -p 10081:10081/tcp \
  -e KUBOARD_ENDPOINT="http://192.168.232.150:9999" \
  -e KUBOARD_AGENT_SERVER_TCP_PORT="10081" \
  -v /root/kuboard-data:/data \
  eipwork/kuboard:v3

 

遇到的问题

1.failed to find plugin “flannel” in path [/opt/cni/bin]，k8sNotReady

过命令在该节点查看相关kubectl日志提示如下错误：

journalctl -u kubelet -f

failed to find plugin “flannel” in path [/opt/cni/bin]

查看 /opt/cni/bin 缺少 flannel

解决办法
需要下载CNI插件：CNI plugins v0.8.6

(flannel文件直接下载)

github下载地址：

https://github.com/containernetworking/plugins/releases/tag/v0.8.6

https://gitee.com/llchaimiyouyan/resources/raw/master/cni-plugins-linux-amd64-v0.8.6.tgz

(在1.0.0版本后CNI Plugins中没有flannel)

下载后通过xftp 上传到Linux /home目录解压

tar zxvf cni-plugins-linux-amd64-v0.8.6.tgz

复制 flannel 到 /opt/cni/bin/

 cp flannel /opt/cni/bin/

节点由NotReady变为Ready

————————————————
版权声明：问题为CSDN博主「奈斯菟咪踢呦」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/qq_34288630/article/details/127772813

2.为什么要关闭swap、selinux、firewalld

部署Kubernetes（k8s）时关闭swap、selinux和firewalld是为了确保集群的稳定性、安全性和正常运行。
关闭Swap：Swap是一种虚拟内存，当物理内存不足时，操作系统将数据转移到磁盘上。在Kubernetes集群中，应用程序的性能和稳定性对内存的需求很高。K8s的各个组件和容器都需要足够的内存来运行，而Swap的使用可能导致性能下降，甚至是应用程序的奔溃。关闭Swap可以确保集群的可预测性和稳定性，避免不必要的磁盘交换。
关闭SELinux（Security-Enhanced Linux）：SELinux是Linux内核的安全模块，用于强化系统的安全性。然而，在Kubernetes环境中，SELinux可能干扰容器与宿主机之间的交互，导致意外的权限问题。K8s使用一种名为"Container Runtime"的组件来运行容器，而SELinux的策略可能会限制容器的正常操作。关闭SELinux可以减少由于安全策略冲突引起的问题，同时K8s本身已经提供了适当的隔离和安全机制。
关闭Firewalld（防火墙）：防火墙是用于保护网络安全的重要组件，但在Kubernetes集群中，可能会干扰集群内部的网络通信。K8s集群内部有许多组件需要相互通信，例如节点之间的Pod通信、Master节点与Worker节点之间的通信等。如果防火墙设置不当，会阻止这些必要的通信，导致集群部署失败或者网络问题。关闭防火墙可以确保K8s集群内部的正常通信，同时需要在K8s的网络配置中设置适当的安全规则。需要注意的是，尽管关闭这些组件可能会带来一些好处，但也可能导致一些安全风险。
关闭SELinux和防火墙可能会降低系统的安全性，因此在执行这些步骤之前，务必考虑集群环境的安全需求，并确保在关闭这些组件之后采取适当的安全措施来保护集群。

 

posted @ 2023-09-10 11:43  柴米油盐哈哈  阅读(246)  评论(0)    收藏  举报