ubuntu 18.04下使用kubeadm安装部署k8s

测试环境：ubuntu18.04

部署目标：部署一个k8s master节点+一个k8s slave节点

安装步骤

1. 准备环境

   x
   cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
   net.bridge.bridge-nf-call-ip6tables = 1
   net.bridge.bridge-nf-call-iptables = 1
   EOF
   sudo sysctl --system
   

   关闭swap

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   swapoff -a
   

   永久关闭swap，编辑/etc/fstab，删除对应行。

    

2. 安装docker

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   # (Install Docker CE)
   ## Set up the repository:
   ### Install packages to allow apt to use a repository over HTTPS
   apt-get update && apt-get install -y \
     apt-transport-https ca-certificates curl software-properties-common gnupg2
   

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   # Add Docker’s official GPG key:
   curl -fsSL http://mirrors.aliyun.com/docker-ce/linux/ubuntu/gpg | apt-key add -
   

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   # Add the Docker apt repository:
   add-apt-repository "deb [arch=amd64] http://mirrors.aliyun.com/docker-ce/linux/ubuntu $(lsb_release -cs) stable"
   

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   apt-get update && apt-get install -y \
     containerd.io=1.2.13-2 \
     docker-ce=5:19.03.11~3-0~ubuntu-$(lsb_release -cs) \
     docker-ce-cli=5:19.03.11~3-0~ubuntu-$(lsb_release -cs)
   

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   # Set up the Docker daemon
   cat > /etc/docker/daemon.json <<EOF
   {
     "exec-opts": ["native.cgroupdriver=systemd"],
     "log-driver": "json-file",
     "log-opts": {
       "max-size": "100m"
     },
     "storage-driver": "overlay2",
     "registry-mirrors": ["https://qpb5oc44.mirror.aliyuncs.com"]
   }
   EOF
   

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   mkdir -p /etc/systemd/system/docker.service.d
   

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   # Restart Docker
   systemctl daemon-reload
   systemctl restart docker
   

    

   添加自启动

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   sudo systemctl enable docker
   

    

3. 安装kubeadm，kubelet，kubectl

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   sudo apt-get update && sudo apt-get install -y apt-transport-https curl
   ​
   curl -s https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo apt-key add -
   ​
   cat <<EOF > /etc/apt/sources.list.d/kubernetes.list
   deb https://mirrors.aliyun.com/kubernetes/apt kubernetes-xenial main
   EOF
   ​
   sudo apt-get update
   sudo apt-get install -y kubelet kubeadm kubectl
   sudo apt-mark hold kubelet kubeadm kubectl
   

4. 初始化master节点（在master机器执行）

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   kubeadm init \
     --apiserver-advertise-address=172.24.151.213 \
     --image-repository registry.aliyuncs.com/google_containers \
     --kubernetes-version=v1.18.3 \
     --service-cidr=10.1.0.0/16 \
     --pod-network-cidr=10.244.0.0/16
   

   如果init失败，可以先kubeadm reset，然后删除所有image，再执行init。

   给当前用户kubectl权限：

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

   此时使用kubectl get node命令查看节点状态，发现还处于NotReady状态。这是因为没安装网络插件。

5. 安装pod网络插件（在master机器执行）

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   kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/v0.12.0/Documentation/kube-flannel.yml
   

   如果安装慢，可以考虑将kube-flannel.yml下载到本地，替换里面的镜像地址quay.io为国内源quay.mirrors.ustc.edu.cn。然后再执行kubectl apply -f kube-flannel.yml。

   通过命令kubectl get pods -A查看当前运行的系统pods。

   此时再通过kubectl get node命令查看节点状态，发现还处于ready状态。

6. 加入node节点（在slave机器执行）

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   kubeadm join 172.24.151.213:6443 --token zuxz7o.by58pol47lm5r802 \
       --discovery-token-ca-cert-hash sha256:150578713a0d7116867cf62fb648c039d42d3b9ac9ba0e8e6201d89967fd98c0
   

7. 测试集群

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   $ kubectl create deployment nginx --image=nginx
   $ kubectl expose deployment nginx --port=80 --type=NodePort 
   

   查看服务状态，得到k8s给nginx分配的端口

   xxxxxxxxxx
   $ kubectl get pod,svc
   

   通过任一节点ip，加上上面得到的端口，即可访问到nginx的主页。

8. 部署dashboard

   下载yaml文件

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   $ wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml -O kubernetes-dashboard.yaml
   

   修改镜像地址，使之能够国内网络访问

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   image: k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.1
   改为
   image: docker.io/mirrorgooglecontainers/kubernetes-dashboard-amd64:v1.10.1
   

   修改service，指定类型

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   spec:
     type: NodePort
     ports:
       - port: 443
         targetPort: 8443
   

   执行yaml文件

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   $ kubectl apply -f kubernetes-dashboard.yaml
   

   通过https://nodeip:nodeport即可访问到界面。

9. 生成dashboard token

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   kubectl create serviceaccount dashboard-admin -n kubernetes-dashboard
   kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kubernetes-dashboard:dashboard-admin
   kubectl describe secrets -n kubernetes-dashboard $(kubectl -n kubernetes-dashboard get secret | awk '/dashboard-admin/{print $1}')
   

    

问题解决

1. 如何删除pod

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     kubectl delete -f kubernetes-dashboard.yaml
   

2. init失败后，如何重新init

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   kubeadm reset
   

   使用docker images查看是否有id相同的image，如果存在，则也需要把这些image删除。

3. dashboard因为证书问题打不开的问题

   创建自签名证书

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   sudo su -
   touch /root/.rnd
   mkdir -p /data/tls && cd /data/tls
   openssl genrsa -out ca.key 2048
   openssl req -new -x509 -key ca.key -out ca.crt -days 3650 -subj "/C=CN/ST=HB/L=WH/O=DM/OU=YPT/CN=CA"
   //生成私钥
   openssl genrsa -out dashboard.key 2048
   

   申请签名请求

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   # ip为dashaboard访问地址ip
   export ip=172.24.151.213
   ​
   openssl req -new -sha256 -key dashboard.key -out dashboard.csr -subj "/C=CN/ST=HB/L=WH/O=DM/OU=YPT/CN=$ip"
   ​
   cat >  dashboard.cnf  <<EOF
   extensions = san
   [san]
   keyUsage = digitalSignature
   extendedKeyUsage = clientAuth,serverAuth
   subjectKeyIdentifier = hash
   authorityKeyIdentifier = keyid,issuer
   subjectAltName = IP:$ip,IP:127.0.0.1,DNS:$ip,DNS:localhost
   EOF
   

   签发证书

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   openssl x509 -req -sha256 -days 3650 -in dashboard.csr -out dashboard.crt -CA ca.crt -CAkey ca.key -CAcreateserial -extfile dashboard.cnf
   

   删除旧kubernetes-dashboard

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   kubectl delete -f kubernetes-dashboard.yaml
   

   修改kubernetes-dashboard.yaml 文件，注释以下行

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

   创建 secret kubernetes-dashboard-certs

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   kubectl create secret generic kubernetes-dashboard-certs --from-file="/data/tls/dashboard.crt,/data/tls/dashboard.key" -n kubernetes-dashboard
   

    

   重新部署dashboard

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   kubectl create -f kubernetes-dashboard.yaml