centos 7 搭建 k8s
环境
Centos 7.2
master 192.168.121.101
node-1 192.168.121.134
node-2 192.168.121.135
Kubernetes集群组件:
– etcd 一个高可用的K/V键值对存储和服务发现系统
– flannel 实现夸主机的容器网络的通信
– kube-apiserver 提供kubernetes集群的API调用
– kube-controller-manager 确保集群服务
– kube-scheduler 调度容器，分配到Node
– kubelet 在Node节点上按照配置文件中定义的容器规格启动容器
– kube-proxy 提供网络代理服务，将service与pod打通。
Kubernetes工作模式server-client，Kubenetes Master提供集中化管理Minions。部署1台Kubernetes Master节点和2台Minion节点
准备工作
关闭selinux
setenforce 0
vim /etc/sysconfig/selinux SELINUX=enforcing 改为 SELINUX=disabled
关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
1.配置阿里云yum源
cat << EOF | tree /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 EOF
一、master 安装配置
1，使用yum安装etcd和kubernetes -master
yum install etcd kubernetes-master -y
2.编辑/etc/etcd/etcd.conf文件
mv /etc/etcd/etcd.conf /etc/etcd/etcd.conf.bak cat << EOF > /etc/etcd/etcd.conf ETCD_DATA_DIR="/var/lib/etcd/default.etcd" ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379" ETCD_NAME="default" ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379" EOF
3.编辑/etc/kubernetes/apiserver文件
mv /etc/kubernetes/apiserver /etc/kubernetes/apiserver.bak
cat << EOF > /etc/kubernetes/apiserver KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0" KUBE_API_PORT="--port=8080" KUBELET_PORT="--kubelet-port=10250" KUBE_ETCD_SERVERS="--etcd-servers=http://127.0.0.1:2379" KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=192.168.121.0/24" KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,ResourceQuota" KUBE_API_ARGS="" EOF
4.设置 etcd、kube-apiserver、kube-controller-manager、kube-scheduler 为开机自启
for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do systemctl start $SERVICES;systemctl enable $SERVICES;systemctl status $SERVICES; done
5.在etcd中定义flannel网络
etcdctl mk /atomic.io/network/config '{"Network":"172.40.0.0/16"}'
注意这里不建议设置172.17这个docker默认网段。删除这个网段用rm，可以etcdctl –help了解这个命令的用法。
二、node节点安装部署
以 node-1 192.168.121.134 为例
1.使用yum安装flannel和kubernetes-node
yum install flannel kubernetes-node -y
2.为flannel网络指定etcd服务，修改/etc/sysconfig/flanneld文件
mv /etc/sysconfig/flanneld /etc/sysconfig/flanneld.bak
cat << EOF > /etc/sysconfig/flanneld FLANNEL_ETCD_ENDPOINTS="http://192.168.121.101:2379" FLANNEL_ETCD_PREFIX="/atomic.io/network" EOF
3.修改/etc/kubernetes/config文件
mv /etc/kubernetes/config /etc/kubernetes/config.bak cat << EOF > /etc/kubernetes/config KUBE_LOGTOSTDERR="--logtostderr=true" KUBE_LOG_LEVEL="--v=0" KUBE_ALLOW_PRIV="--allow-privileged=false" KUBE_MASTER="--master=http://192.168.121.101:8080" EOF
4.修改node节点配置文件/etc/kubernetes/kubelet
mv /etc/kubernetes/kubelet /etc/kubernetes/kubelet.bak cat << EOF > /etc/kubernetes/kubelet KUBELET_ADDRESS="--address=0.0.0.0" KUBELET_PORT="--port=10250" KUBELET_HOSTNAME="--hostname-override=192.168.121.134" KUBELET_API_SERVER="--api-servers=http://192.168.121.101:8080" KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest" KUBELET_ARGS="" EOF
5，配置完node1，2后，在所有Node节点上启动flanneld，docker，kube-proxy,kubelet服务，并设置开机启动。这里强调一下，一定要注意etcd—->flannel—–>docker的先后启动顺序,否则会导致pod里边的ip会和其他node节点的pod不在一个网段，通信就有问题。
for SERVICES in flanneld docker kube-proxy kubelet;do systemctl start $SERVICES;systemctl enable $SERVICES;systemctl status $SERVICES; done
三、验证集群状态
master执行下面命令
kubectl get node
NAME STATUS AGE
192.168.121.134 Ready 15s
192.168.121.135 Ready 12s
参考 https://www.cnblogs.com/ajianboke/p/10916133.html
问题汇总
1.docker 启动失败报错 unable to configure the Docker daemon with file /etc...n: EOF\n
解决方法
在 /etc/docker/daemon.json文件里加一个 {} 就解决了
2. kubectl get pod 出现错误【The connection to the server localhost:8080 was refused - did you specif...
解决方法
echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile source ~/.bash_profile
重启 kube-apiserver
systemctl restart kube-apiserver
3.etcd启动不起来
解决方法
（1）删除 data-dir 文件
rm -rf /var/lib/etcd/*
