目標：使用kubeadm部署kubernetes叢集

環境：CentOS 7

步驟：基礎環境配置->kubernetes安裝前設定(源、映象及相關配置)->kubeadm部署(master)->啟用基於flannel的Pod網路->kubeadm加入node節點->dashboard元件安裝與使用->heapster監控元件安裝與使用->訪問測試

1.基礎環境配置

master和所有node節點都需要進行基礎環境配置。

(1)net相關項配置

設定ipv4轉發：

vim /etc/sysctl.d/k8s.conf：增加一行 net.ipv4.ip_forward = 1

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

centos7下net-bridge設定：

echo 1 > /proc/sys/net/bridge/bridge-nf-call-iptables
echo 1 > /proc/sys/net/bridge/bridge-nf-call-ip6tables

(2)docker安裝

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

檢視docker版本：

yum list docker-ce.x86_64 --showduplicates | sort -r

本文使用Kubernetes 1.10版本，因此選用驗證過的17.03.2docker版本。

yum makecache fast

yum install -y --setopt=obsoletes=0 docker-ce-17.03.2.ce-1.el7.centos

啟動docker：

systemctl enable docker

systemctl start docker

docker 1.13以上版本預設禁用iptables的forward呼叫鏈，因此需要執行開啟命令：

iptables -P FORWARD ACCEPT

2.kubernetes安裝前設定(源、映象及相關配置)

配置源路徑：使用國內的阿里源

vim /etc/yum.repos.d/kubernetes.repo

[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
       http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
 

docker映象拉取，因為預設拉取路徑為google，因此使用國內映象。

(1)master節點

vim k8s.sh

docker pull cnych/kube-apiserver-amd64:v1.10.0
docker pull cnych/kube-scheduler-amd64:v1.10.0
docker pull cnych/kube-controller-manager-amd64:v1.10.0
docker pull cnych/kube-proxy-amd64:v1.10.0
docker pull cnych/k8s-dns-kube-dns-amd64:1.14.8
docker pull cnych/k8s-dns-dnsmasq-nanny-amd64:1.14.8
docker pull cnych/k8s-dns-sidecar-amd64:1.14.8
docker pull cnych/etcd-amd64:3.1.12
docker pull cnych/flannel:v0.10.0-amd64
docker pull cnych/pause-amd64:3.1
 
docker tag cnych/kube-apiserver-amd64:v1.10.0 k8s.gcr.io/kube-apiserver-amd64:v1.10.0
docker tag cnych/kube-scheduler-amd64:v1.10.0 k8s.gcr.io/kube-scheduler-amd64:v1.10.0
docker tag cnych/kube-controller-manager-amd64:v1.10.0 k8s.gcr.io/kube-controller-manager-amd64:v1.10.0
docker tag cnych/kube-proxy-amd64:v1.10.0 k8s.gcr.io/kube-proxy-amd64:v1.10.0
docker tag cnych/k8s-dns-kube-dns-amd64:1.14.8 k8s.gcr.io/k8s-dns-kube-dns-amd64:1.14.8
docker tag cnych/k8s-dns-dnsmasq-nanny-amd64:1.14.8 k8s.gcr.io/k8s-dns-dnsmasq-nanny-amd64:1.14.8
docker tag cnych/k8s-dns-sidecar-amd64:1.14.8 k8s.gcr.io/k8s-dns-sidecar-amd64:1.14.8
docker tag cnych/etcd-amd64:3.1.12 k8s.gcr.io/etcd-amd64:3.1.12
docker tag cnych/flannel:v0.10.0-amd64 quay.io/coreos/flannel:v0.10.0-amd64
docker tag cnych/pause-amd64:3.1 k8s.gcr.io/pause-amd64:3.1

chmod +x k8s.sh，然後執行./k8s.sh

docker images檢視當前映象：

執行安裝命令：

yum install -y kubelet kubeadm kubectl

配置kubelet：

docker info | grep Cgroup

修改k8s配置檔案：vim /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

修改為cgroupfs，與docker匹配

Environment="KUBELET_CGROUP_ARGS=--cgroup-driver=cgroupfs"

關閉swap：

Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false"

(2)Node節點

vim k8s-node.sh

docker pull cnych/kube-proxy-amd64:v1.10.0
docker pull cnych/flannel:v0.10.0-amd64
docker pull cnych/pause-amd64:3.1
docker pull cnych/kubernetes-dashboard-amd64:v1.8.3
docker pull cnych/heapster-influxdb-amd64:v1.3.3
docker pull cnych/heapster-grafana-amd64:v4.4.3
docker pull cnych/heapster-amd64:v1.4.2
docker pull cnych/k8s-dns-kube-dns-amd64:1.14.8
docker pull cnych/k8s-dns-dnsmasq-nanny-amd64:1.14.8
docker pull cnych/k8s-dns-sidecar-amd64:1.14.8
 
docker tag cnych/flannel:v0.10.0-amd64 quay.io/coreos/flannel:v0.10.0-amd64
docker tag cnych/pause-amd64:3.1 k8s.gcr.io/pause-amd64:3.1
docker tag cnych/kube-proxy-amd64:v1.10.0 k8s.gcr.io/kube-proxy-amd64:v1.10.0
docker tag cnych/kubernetes-dashboard-amd64:v1.8.3 k8s.gcr.io/kubernetes-dashboard-amd64:v1.8.3
docker tag cnych/heapster-influxdb-amd64:v1.3.3 k8s.gcr.io/heapster-influxdb-amd64:v1.3.3
docker tag cnych/heapster-grafana-amd64:v4.4.3 k8s.gcr.io/heapster-grafana-amd64:v4.4.3
docker tag cnych/heapster-amd64:v1.4.2 k8s.gcr.io/heapster-amd64:v1.4.2
docker tag cnych/k8s-dns-kube-dns-amd64:1.14.8 k8s.gcr.io/k8s-dns-kube-dns-amd64:1.14.8
docker tag cnych/k8s-dns-dnsmasq-nanny-amd64:1.14.8 k8s.gcr.io/k8s-dns-dnsmasq-nanny-amd64:1.14.8
docker tag cnych/k8s-dns-sidecar-amd64:1.14.8 k8s.gcr.io/k8s-dns-sidecar-amd64:1.14.8

此處包含了dashboard和heapster相關映象。

執行過程與master節點相同。

3.kubeadm部署(master)

在master節點執行初始化命令：

kubeadm init --kubernetes-version=v1.10.3 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.0.29

之後按說明執行mkdir -p $HOME/.kube等命令。

kubectl get cs檢視叢集狀態：

4.啟用基於flannel的Pod網路

啟動flannel：kubectl apply -f  kube-flannel.yml

kubectl get pods --all-namespaces檢視狀態：

5.kubeadm加入node節點

在node節點上執行：

kubeadm join 192.168.0.29:6443 --token xxxx --discovery-token-ca-cert-hash xxxx

在master節點上執行：

kubectl get nodes

6.dashboard元件安裝與使用

建立admin賬戶配置檔案：kubernetes-dashboard-admin.rbac.yaml

---
apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-admin
  namespace: kube-system
 
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: kubernetes-dashboard-admin
  labels:
    k8s-app: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard-admin
  namespace: kube-system

執行：kubectl create -f kubernetes-dashboard-admin.rbac.yaml

檢視kubernete-dashboard-admin的token：

kubectl -n kube-system get secret | grep kubernetes-dashboard-admin

其中的token即為dashboard登入用的令牌。

修改現有dashboard訪問方式為NodePort：修改type型別為NodePort

kubectl -n kube-system edit service kubernetes-dashboard

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: 2018-05-29T09:09:30Z
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
  resourceVersion: "2647"
  selfLink: /api/v1/namespaces/kube-system/services/kubernetes-dashboard
  uid: fe971993-631f-11e8-9154-fa163e598eb8
spec:
  clusterIP: 10.101.128.69
  externalTrafficPolicy: Cluster
  ports:
  - nodePort: 30269
    port: 443
    protocol: TCP
    targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard
  sessionAffinity: None
  type: NodePort
status:
  loadBalancer: {}

7.heapster監控元件安裝與使用

在master節點下載heapster配置檔案：

修改heapster.yaml，將版本改為1.4.2

vim k8s-heapster.sh

docker pull cnych/heapster-influxdb-amd64:v1.3.3
docker pull cnych/heapster-grafana-amd64:v4.4.3
docker pull cnych/heapster-amd64:v1.4.2
 
docker tag cnych/heapster-influxdb-amd64:v1.3.3 k8s.gcr.io/heapster-influxdb-amd64:v1.3.3
docker tag cnych/heapster-grafana-amd64:v4.4.3 k8s.gcr.io/heapster-grafana-amd64:v4.4.3
docker tag cnych/heapster-amd64:v1.4.2 k8s.gcr.io/heapster-amd64:v1.4.2

執行k8s-heapster.sh下載映象

啟用heapster：

cd ~/k8s/heapster/

kubectl create -f ./

8.訪問測試

檢視kube-system pod是否都正常執行：

kubectl get pods -n kube-system

選擇令牌登入：

主介面：