安装Kubernetes（K8S）
用kubeadm的方法安装k8s：
环境： 三台主机 一台master 俩台node
三台主机的硬件需求：
·最少2G内存
·最少2个CPU
更改hosts文件：
[root@master ~]# cat /etc/hosts 192.168.172.134 master 192.168.172.135 node1 192.168.172.136 node2
关闭swap和selinux 防火墙（实验环境 ） 并设置swap内核参数
永久关闭swap 注释掉就好
cat /etc/fstab #/dev/mapper/cl-swap swap swap defaults 0 0
关闭selinux
vim /etc/selinux/config
SELINUX=disabled ##更改成disabled
关闭防火墙：
systemctl stop firewalld
systemctl disable firewalld
设置swap内核参数：
vim /etc/sysctl.conf vm.swappiness = 0
重新加载
swapoff -a
设置桥接网：
先加载模块： modprobe br_netfilter
cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 EOF
重新加载并查看：
sysctl -p
安装docker三台都需要操作
yum install -y yum-utils device-mapper-persistent-data lvm2 yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo yum makecache fast yum -y install docker-ce-18.06.3.ce-3.el7
开启服务并且自启动：
systemctl start docker
systemctl enable docker
三台都需要安装：
[root@master ~]# cat /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/ enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
下载kubernetes
yum -y install kubelet-1.17.0 kubeadm-1.17.0 kubectl-1.17.0
开启服务：
systemctl start kubelet.service && systemctl enable kubelet
下载镜像，打上标签，删除之前的
[root@master ~]# vim caoyi.sh
caoyi=registry.aliyuncs.com/google_containers
source=k8s.gcr.io
docker pull $caoyi/kube-apiserver:v1.17.0
docker pull $caoyi/kube-controller-manager:v1.17.0
docker pull $caoyi/kube-scheduler:v1.17.0
docker pull $caoyi/kube-proxy:v1.17.0
docker pull $caoyi/pause:3.1
docker pull $caoyi/etcd:3.4.3-0
docker pull $caoyi/coredns:1.6.5
docker tag $caoyi/kube-apiserver:v1.17.0 $source/kube-apiserver:v1.17.0
docker tag $caoyi/kube-controller-manager:v1.17.0 $source/kube-controller-manager:v1.17.0
docker tag $caoyi/kube-scheduler:v1.17.0 $source/kube-scheduler:v1.17.0
docker tag $caoyi/kube-proxy:v1.17.0 $source/kube-proxy:v1.17.0
docker tag $caoyi/pause:3.1 $source/pause:3.1
docker tag $caoyi/etcd:3.4.3-0 $source/etcd:3.4.3-0
docker tag $caoyi/coredns:1.6.5 $source/coredns:1.6.5
docker rmi $caoyi/kube-apiserver:v1.17.0
docker rmi $caoyi/kube-controller-manager:v1.17.0
docker rmi $caoyi/kube-scheduler:v1.17.0
docker rmi $caoyi/kube-proxy:v1.17.0
docker rmi $caoyi/pause:3.1
docker rmi $caoyi/etcd:3.4.3-0
docker rmi $caoyi/coredns:1.6.5
下载flannel：
docker pull quay.io/coreos/flannel:v0.12.0-adm64
三台主机都需要这样做
配置网络：
[root@master ~]# mkdir -p /etc/cni/net.d/ [root@master ~]# cat /etc/cni/net.d/10-flannel.conf {"name":"cbr0","type":"flannel","delegate":{"isDefaultGateway":true}} [root@master ~]# mkdir /usr/share/oci-umount/oci-umount.d -p [root@master ~]# mkdir /run/flannel/ [root@master ~]# cat /run/flannel/subnet.env FLANNEL_NETWORK=10.244.0.0/16 FLANNEL_SUBNET=10.244.0.1/24 FLANNEL_MTU=1450 FLANNEL_IPMASQ=true
初始化 在master主机上：
kubeadm init --kubernetes-version=v1.17.0 --apiserver-advertise-address 192.168.172.134 --pod-network-cidr 10.244.0.0/16
初始化完成后按照提示在master创建文件
mkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config
按照提示将网络部署到集群
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
因为网址是国外的可能无法访问，我把下载好的yml文件传到github上，方便下载，然后把其他的两个节点加入集群
git clone https://github.com/mrlxxx/kube-flannel.yml.git kubectl apply -f kube-flannel.yml
kubeadm join 192.168.172.134:6443 --token nwnany.7rvdbwfm4wjtxa62 --discovery-token-ca-cert-hash sha256:c44ea7dcf98f5611a34d239dd2fc3420ac4e2993b7aa874d70c01f90f1f8fe60
注意：如果出现节点NotReady的状况，可按照下面的方式进行配置（三台主机都需要配置）： # mkdir -p /etc/cni/net.d/ # cat <<EOF> /etc/cni/net.d/10-flannel.conf { "name": "cbr0", "type": "flannel", "delegate": { "isDefaultGateway": true } } EOF
[root@master ~]# kubectl get cs NAME STATUS MESSAGE ERROR controller-manager Healthy ok scheduler Healthy ok etcd-0 Healthy {"health":"true"}