使用Kubeadm 安装k8s集群

#!/bin/sh

systemctl stop firewalld && systemctl disable firewalld
&& sed -i s/“SELINUX=enforcing”/“SELINUX=disabled”/g /etc/selinux/config
&& sed -i s/"^SELINUXTYPE=targeted"/""/g /etc/selinux/config
&& setenforce 0

cat < /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
EOF

swapoff -a

sed -i ‘/swap/s/^/#/’ /etc/fstab

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

yum install -y yum-utils device-mapper-persistent-data lvm2

yum-config-manager
–add-repo
https://download.docker.com/linux/centos/docker-ce.repo

yum makecache fast

yum install -y --setopt=obsoletes=0
docker-ce-18.06.1.ce-3.el7

systemctl start docker && systemctl enable docker

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

#配置docker代理
sed -i ‘/ExecStart/i\EnvironmentFile=/etc/sysconfig/docker’ /lib/systemd/system/docker.service

cat < /etc/sysconfig/docker
HTTP_PROXY=http://127.0.0.1:38118
HTTPS_PROXY=http://127.0.0.1:38118
EOF

systemctl daemon-reload && systemctl restart docker

echo “proxy=http://127.0.0.1:38118” >>/etc/yum.conf

yum -y makecache fast

yum install -y kubelet kubeadm kubectl

systemctl enable kubelet.service

kubeadm init
–kubernetes-version=v1.12.0
–pod-network-cidr=192.168.0.0/16
–apiserver-advertise-address=172.16.207.11

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

#Network install
kubectl apply -f
https://docs.projectcalico.org/v3.2/getting-started/kubernetes/installation/hosted/etcd.yaml

kubectl apply -f
https://docs.projectcalico.org/v3.2/getting-started/kubernetes/installation/rbac.yaml

kubectl apply -f
https://docs.projectcalico.org/v3.2/getting-started/kubernetes/installation/hosted/calico.yaml

#集群初始化如果遇到问题，可以使用下面的命令进行清理：

kubeadm reset
ifconfig cni0 down
ip link delete cni0
ifconfig flannel.1 down
ip link delete flannel.1
rm -rf /var/lib/cni/

从集群中移除Node

master 上执行

kubectl drain node2 --delete-local-data --force --ignore-daemonsets
kubectl delete node node2

在node2上执行：

kubeadm reset
ifconfig cni0 down
ip link delete cni0
ifconfig flannel.1 down
ip link delete flannel.1
rm -rf /var/lib/cni/

在node1上执行：

kubectl delete node node2

测试DNS

kubectl run curl --image=radial/busyboxplus:curl -it
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
If you don't see a command prompt, try pressing enter.
[ root@curl-5cc7b478b6-r997p:/ ]$ 

命令执行成功将直接进入到容器中
进入后执行nslookup kubernetes.default确认解析正常:

nslookup kubernetes.default
Server:    10.96.0.10
Address 1: 10.96.0.10 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes.default
Address 1: 10.96.0.1 kubernetes.default.svc.cluster.local