Kubernetes是一个基于容器技术的分布式架构,可以实现集群规模化部署,容器的部署以及对容器的操作(服务版本更新,迁移,调试)

下面是通过kubeadm快速安装Kubernetes集群.

配置Yum源:

# cat magina-k8s.repo
[magina-k8s]
name=Magina K8s Repository
baseurl=https://cdn.yinnote.com/centos7/magina-k8s
enabled=1
gpgcheck=0
gpgkey=https://cdn.yinnote.com/keys/rpm.public.key

安装rpm包:

yum makecache
yum intall -y docker
systemctl enable docker && systemctl start docker
yum install -y kubelet-1.6.1 kubectl-1.6.1 kubeadm-1.6.1
systemctl enable kubelet && systemctl start kubelet

配置加速器:这个加速器是我自己的daocloud地址

# pwd
/etc/docker
# cat daemon.json
{"registry-mirrors": ["http://62839702.m.daocloud.io"],
  "registry-mirror":[
    "https://registry.docker-cn.com"
  ],
  "insecure-registries":[
    "www.sholck.top:5000"
  ]
}
#systemctl daemon-reload && systemctl restart docker

编写脚本:(sholck是我的Docker Hub帐号 )

# cd /opt/
# cat k8s-docker-images.sh
# 创建镜像下载脚本
#############################################
# 添加需要的镜像
images=(
pause-amd64:3.0
kube-proxy-amd64:v1.6.1
kube-scheduler-amd64:v1.6.1
kube-controller-manager-amd64:v1.6.1
kube-apiserver-amd64:v1.6.1
etcd-amd64:3.0.17
k8s-dns-sidecar-amd64:1.14.1
k8s-dns-kube-dns-amd64:1.14.1
k8s-dns-dnsmasq-nanny-amd64:1.14.1
)

for imageName in ${images[@]} ; do
docker pull sholck/$imageName
docker tag sholck/$imageName gcr.io/google_containers/$imageName
docker rmi sholck/$imageName
done
#############################################

执行脚本实现拉取镜像,清理

执行启动kubelet并安装集群

#kubeadm reset
#systemctl start kubelet
#kubeadm init --kubernetes-version=v1.6.1 --apiserver-advertise-address yourIP
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[init] Using Kubernetes version: v1.6.1
[init] Using Authorization mode: RBAC
[preflight] Running pre-flight checks
[preflight] WARNING: docker version is greater than the most recently validated version. Docker version: 1.13.1. Max validated version: 1.12
[preflight] Starting the kubelet service
[certificates] Generated CA certificate and key.
[certificates] Generated API server certificate and key.
[certificates] API Server serving cert is signed for DNS names [jiche kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 47.94.201.186]
[certificates] Generated API server kubelet client certificate and key.
[certificates] Generated service account token signing key and public key.
[certificates] Generated front-proxy CA certificate and key.
[certificates] Generated front-proxy client certificate and key.
[certificates] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf"
[apiclient] Created API client, waiting for the control plane to become ready
[apiclient] All control plane components are healthy after 25.213093 seconds
[apiclient] Waiting for at least one node to register
[apiclient] First node has registered after 5.202103 seconds
[token] Using token: e60caf.86ab3a734f1293ee
[apiconfig] Created RBAC rules
[addons] Created essential addon: kube-proxy
[addons] Created essential addon: kube-dns

Your Kubernetes master has initialized successfully!

To start using your cluster, you need to run (as a regular user):

  sudo cp /etc/kubernetes/admin.conf $HOME/
  sudo chown $(id -u):$(id -g) $HOME/admin.conf
  export KUBECONFIG=$HOME/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:
  http://kubernetes.io/docs/admin/addons/

You can now join any number of machines by running the following on each node
as root:
  kubeadm join --token e60caf.86ab3a734f1293ee yourIP:6443

安装Node节点,加入集群.

# kubeadm join --token e60caf.86ab3a734f1293ee yourIP:6443
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[preflight] Running pre-flight checks
[preflight] WARNING: docker version is greater than the most recently validated version. Docker version: 1.13.1. Max validated version: 1.12
[preflight] WARNING: hostname "chejian" could not be reached
[preflight] WARNING: hostname "chejian" lookup chejian on 59.49.49.49:53: no such host
[preflight] Starting the kubelet service
[discovery] Trying to connect to API Server "yourIP:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://yourIP:6443"
[discovery] Cluster info signature and contents are valid, will use API Server "https://yourIP:6443"
[discovery] Successfully established connection with API Server "yourIP:6443"
[bootstrap] Detected server version: v1.6.1
[bootstrap] The server supports the Certificates API (certificates.k8s.io/v1beta1)
[csr] Created API client to obtain unique certificate for this node, generating keys and certificate signing request
[csr] Received signed certificate from the API server, generating KubeConfig...
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"
Node join complete:
* Certificate signing request sent to master and response
received.
* Kubelet informed of new secure connection details.

Run 'kubectl get nodes' on the master to see this machine join.

master执行kubectl get nodes命令出现以下错误:

# kubectl get nodes
The connection to the server localhost:8080 was refused - did you specify the right host or port? 

问题来源:

查看 /etc/kubernetes/manifests/kube-apiserver.yaml中：–insecure-port=0
kube-apiserver的选项–insecure-port=0，也就是说kubeadm 1.6.0初始化的集群，kube-apiserver没有监听默认的http 8080端口。kube-apiserver只监听了https的6443端口。

解决方案:

在/etc/profile文件中追加:

export KUBECONFIG=/etc/kubernetes/admin.conf 
source /etc/profile

重行执行命令:

# kubectl get nodes
NAME      STATUS     ROLES     AGE       VERSION
chejian   NotReady            13m       v1.6.1
jiche     NotReady   master   14m       v1.6.1