使用kubeadm安装kubenetes

一、环境

关闭防火墙和selinux

禁用swap

服务器配置，至少2核2G

所有节点

#所有节点

echo net.bridge.bridge-nf-call-iptables =   >>/etc/sysctl.conf
echo net.ipv4.ip_forward= >>/etc/sysctl.conf
echo net.bridge.bridge-nf-call-iptables= >>/etc/sysctl.conf
echo net.bridge.bridge-nf-call-ip6tables= >>/etc/sysctl.conf
echo vm.swappiness= >>/etc/sysctl.conf

sysctl -p

#有swap的话要关闭

#swapoff -a
  #sed -i '/swap/s/^/#/' /etc/fstab

#关闭firewalld
systemctl stop firewalld
systemctl disable firewalld
sed -i 's/=enforcing/=disabled/g' /etc/selinux/config

#ipvs相关
cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod  /etc/sysconfig/modules/ipvs.modules
bash /etc/sysconfig/modules/ipvs.modules
lsmod | grep -e ip_vs -e nf_conntrack_ipv4

#配置源
cd /etc/yum.repos.d/
wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
cat>>/etc/yum.repos.d/kubrenetes.repo<<EOF
[kubernetes]
name=Kubernetes Repo
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
gpgcheck=
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
EOF

#下载服务
#查看docker-ce版本
yum list docker-ce.x86_64  --showduplicates |sort -r
#k8s1.14最高支持18.09版本的docker
#yum install -y --setopt=obsoletes= docker-ce-18.09.-.el7
yum install  kubelet kubeadm kubectl -y
yum -y install ipvsadm ipset

master节点执行操作

#启动服务
systemctl   restart docker
systemctl   enable docker
systemctl enable kubelet && systemctl start kubelet

#kubeadm初始化
kubeadm init  --kubernetes-version=v1.18.0  --pod-network-cidr=10.244.0.0/16 --service-cidr=10.96.0.0/12
#国内环境安装
# kubeadm init  --kubernetes-version=v1.18.0  --pod-network-cidr=10.244.0.0/16 --service-cidr=10.96.0.0/12 --image-repository='registry.cn-hangzhou.aliyuncs.com/google_containers'

#记录初始化后的kubeadm join 信息
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

#安装flannel网络（也可以安装其他网络）
#wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
#kubectl  apply -f kube-flannel.yml
#安装calico网络
wget https://docs.projectcalico.org/manifests/calico.yaml
#更换网段
sed -i "s#192.168.0.0/16#10.244.0.0/16#g" calico.yaml
#导入
kubectl  apply -f calico.yaml

　　

node节点操作

#启动服务
systemctl   restart docker
systemctl   enable docker

#执行master上显示的kubeadm join命令 (类似如下)
kubeadm join 172.31.250.160:6443 --token fx3ua3.4cxlvfnbrhiwpnj8     --discovery-token-ca-cert-hash sha256:1ac1ece9c7b61fb88208680ba9e864d3a496a81be4bc2212833327b14d0991bf

　　

在master端使用kubectl get node 查看即可

[root@k8s-m ~]# kubectl  get node
NAME    STATUS   ROLES    AGE     VERSION
k8s-m   Ready    master   12m     v1.18.0
node    Ready    <none>   9m22s   v1.18.0

　　

kube-proxy 开启 ipvs

改ConfigMap的kube-system/kube-proxy中的config.conf，mode: “ipvs”

[root@k8s-m ~]kubectl edit cm kube-proxy -n kube-system
......
ipvs:
      excludeCIDRs: null
      minSyncPeriod: 0s
      scheduler: ""
      strictARP: false
      syncPeriod: 0s
      tcpFinTimeout: 0s
      tcpTimeout: 0s
      udpTimeout: 0s
    kind: KubeProxyConfiguration
    metricsBindAddress: ""
    mode: "ipvs"  #改成这样

删除原先的kube-proxy的pod

[root@k8s-m ~]#  kubectl get pods -n kube-system|grep proxy
kube-proxy-94cdw                           /     Running             102m
kube-proxy-sgdzw                           /     Running             45m
[root@k8s-m ~]# kubectl get pod -n kube-system | grep kube-proxy | awk '{system("kubectl delete pod "$1" -n kube-system")}'
pod "kube-proxy-94cdw" deleted
pod "kube-proxy-sgdzw" deleted
[root@k8s-m ~]# kubectl get pods -n kube-system|grep proxy
kube-proxy-pmntz                           1/1     Running   0          56s
kube-proxy-xbxxb                           1/1     Running   0          58

使用ipvsadm测试，可以查看之前创建的Service已经使用LVS创建了集群

[root@k8s-m ~]# ipvsadm -Ln
IP Virtual Server version 1.2. (size=)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.96.0.1: rr
  -> 10.0.0.100:              Masq
TCP  10.96.0.10: rr
  -> 10.244.167.129:            Masq
  -> 10.244.167.130:            Masq
TCP  10.96.0.10: rr
  -> 10.244.167.129:          Masq
  -> 10.244.167.130:          Masq
UDP  10.96.0.10: rr
  -> 10.244.167.129:            Masq
  -> 10.244.167.130:            Masq