kubeadm 部署 kubernetes 1.23.1集群

集群架构

hostname	os version	ip	cpu	men
master	centos 7.8	192.168.11.186	6	8g
node1	centos 7.8	192.168.11.184	4	4g
node2	centos 7.8	192.168.11.183	4	4g

节点配置前准备

1.开启免密钥认证
$ ssh-keygen
$ ssh-coyid node1,node2
2.编辑/etc/hosts
192.168.11.186 master
192.168.11.184 node1
192.168.11.183 node2
$ scp /etc/hosts  node1:/etc/
$ scp /etc/hosts  node2:/etc/
3.编辑 /etc/sysctl.d/k8s.conf 将流量传递到iptables链
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward                 = 1
$ sysctl --system
$ scp /etc/sysctl.d/k8s.conf  node1:/etc/
$ scp /etc/sysctl.d/k8s.conf  node2:/etc/
4.关闭防火墙
for i in `cat /etc/hosts|awk '{print $2}'`;
do
ssh $i systemctl stop firewalld; systemctl disabled firewalld
done
5.关闭SELINX
for i in `cat /etc/hosts|awk '{print $2}'`;
do
ssh $i setenforce 0
ssh $i sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
done

部署docker

#一下步骤三个节点都需要
1.安装驱动工具
yum install -y yum-utils    device-mapper-persistent-data   lvm2
2.添加docker源
yum-config-manager    --add-repo    "http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo"
3.启用源
yum-config-manager --enable docker-ce-nightly
4.安装docker
yum install docker-ce docker-ce-cli containerd.io -y
5.启动docker
systemctl enable docker && systemctl start docker

部署kubernetes

#一下步骤三个节点都需要
1.添加源
vim /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
2.安装工具
yum install kubeadm kubelet kubectl -y
3.开机自启kubelet
systemctl enable kubelet

master初始化 kubernetes

$ kubeadm init  --apiserver-advertise-address=192.168.11.186  --image-repository \
   registry.aliyuncs.com/google_containers  --kubernetes-version=v1.23.1   \
   --service-cidr=10.96.0.0/16  --pod-network-cidr=10.244.0.0/16
#输出一下信息
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/

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

kubeadm join 192.168.11.186:6443 --token 0fq2s6********* \
        --discovery-token-ca-cert-hash sha256:aa861aabecf********************
2.部署flannel网络插件
$ kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
#注 有时应网络问题不能访问这个地址
添加dns >>/etc/hosts,或者提前下载
185.199.110.133  raw.githubusercontent.com

node节点jojn

$ kubeadm join 192.168.11.186:6443 --token 0fq2s6********* \
        --discovery-token-ca-cert-hash sha256:aa861aabecf

查看集群信息

$ kubectl get pods --all-namespaces
NAMESPACE     NAME                            READY   STATUS    RESTARTS   AGE
kube-system   coredns-6d8c4cb4d-6q2l8         1/1     Running   0          30m
kube-system   coredns-6d8c4cb4d-vgtr4         1/1     Running   0          30m
kube-system   etcd-master                     1/1     Running   0          31m
kube-system   kube-apiserver-master           1/1     Running   0          31m
kube-system   kube-controller-manager-master   1/1     Running   0          31m
kube-system   kube-flannel-ds-6s4mn           1/1     Running   0          27m
kube-system   kube-flannel-ds-nbc8f           1/1     Running   0          27m
kube-system   kube-flannel-ds-rpp6h           1/1     Running   0          27m
kube-system   kube-proxy-4cfh2                1/1     Running   0          30m
kube-system   kube-proxy-nfbgk                1/1     Running   0          30m
kube-system   kube-proxy-vj8m4                1/1     Running   0          30m
kube-system   kube-scheduler-master           1/1     Running   0          31m

$ kubectl get nodes
NAME         STATUS   ROLES                  AGE   VERSION
master   Ready    control-plane,master       31m   v1.23.1
node1        Ready    <none>                 31m   v1.23.1
node2        Ready    <none>                 32m   v1.23.1
$ kubectl get namespace
NAME              STATUS   AGE
default           Active   38m
kube-node-lease   Active   38m
kube-public       Active   38m
kube-system       Active   38m

测试

1.创建pod
$ kubectl create deployment nginx --image=nginx
$ kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-85b98978db-njf42   1/1     Running   0          32s
2.修改pod副本数
$ kubectl scale deployment nginx --replicas=3
$ kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-85b98978db-88pmq   1/1     Running   0          27s
nginx-85b98978db-ksdzb   1/1     Running   0          27s
nginx-85b98978db-njf42   1/1     Running   0          8m49s
3.暴露端口
$ kubectl expose deployment nginx --port=80 --type=NodePort
$ kubectl get services
NAME         TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.96.0.1      <none>        443/TCP        48m
nginx        NodePort    10.96.72.198   <none>        80:32335/TCP   5m2s
$ curl 10.96.72.198
<h1>Welcome to nginx!</h1>
4. 常用命令
kubectl cluster-info #获取集群信息
kubectl api-resources #  查看资源
kubectl get nodes #  查看node节点
kubectl get pods #  查看pod
kubectl get pods -n kube-system #  查看命名空间kube-system下的pod

遇到的问题

image.png

错误信息
“Failed to run kubelet” err=“failed to run Kubelet: misconfiguration: kubelet cgroup driver: “systemd” is different from dock…er: “cgroupfs””
原因
docker和kubernetes所使用的cgroup不一致导致

# cat /etc/docker/daemon.json
{
  "registry-mirrors": ["https://yours.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}

重启docker 重新kubeadm init && kubectl join