輕松加愉快的 Kubernetes 安裝教程

作者:無聊的學習者

來源:見文末

在國內安裝 K8S，一直是大家很頭痛的問題，各種麻煩，關鍵是還不知道需要下載什麽工具。蛋疼。而且大部分國內教程要麽太老，要麽太挫。今天就來告訴大家如何在國內愉快的安裝K8S。

安裝環境

使用的是 kubeadm 進行安裝，過程基本安裝官方教程來的。

雖然寫的是阿裏雲 VPC，但是虛擬機也支持。影響不大。

如果僅僅是本地安裝玩一玩，都可以配置成1核1G。

接下來的過程，如果有FQ主機的情況，按照流程走就可以，沒有的話直接看下載好的結果就可以了。

安裝過程

安裝過程基本包括下載軟件，下載鏡像，主機配置，啟動 Master 節點，配置網絡，啟動 Node 節點。

下載軟件

這個步驟有能力的人可以直接按照步驟來，沒有的話可以使用我打包好的1.6.2軟件包。

首先在自己的主機配置K8S源。

cat <<EOF > /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

配置好後，下載軟件包

yum install -y -downloadonly kubelet kubeadm kubectl kubernetes-cni

將下載好的所有 RPM 打包，發回到本地。這樣就完成了K8S軟件包的下載了。

下載好的 RPM:

https://pan.baidu.com/s/1clIpjC cp6h

下載鏡像

下載鏡像可以直接使用我提供的腳本，前提是要能連外網。我自己也已經下載過一份了。提供給大家使用。

#!/usr/bin/env bash

images=(
kube-proxy-amd64:v1.6.2
kube-controller-manager-amd64:v1.6.2
kube-apiserver-amd64:v1.6.2
kube-scheduler-amd64:v1.6.2
kubernetes-dashboard-amd64:v1.6.0
k8s-dns-sidecar-amd64:1.14.1
k8s-dns-kube-dns-amd64:1.14.1
k8s-dns-dnsmasq-nanny-amd64:1.14.1
etcd-amd64:3.0.17
pause-amd64:3.0
)

for imageName in ${images[@]} ; do
docker pull gcr.io/google_containers/$imageName
docker tag gcr.io/google_containers/$imageName registry.cn-beijing.aliyuncs.com/bbt_k8s/$imageName
docker push registry.cn-beijing.aliyuncs.com/bbt_k8s/$imageName
done

quay.io/coreos/flannel:v0.7.0-amd64
docker tag quay.io/coreos/flannel:v0.7.0-amd64 registry.cn-beijing.aliyuncs.com/bbt_k8s/flannel:v0.7.0-amd64
docker push registry.cn-beijing.aliyuncs.com/bbt_k8s/flannel:v0.7.0-amd64

關於這個腳本我解釋一下。這個腳本是下載常用的鏡像，然後回傳到國內的源上，可以將registry.cn-beijing.aliyuncs.com/bbt_k8s改成你自己的地址，必須先用docker login 進行登錄，否則可能會出現權限認證錯誤。推薦使用阿裏雲，網易的服務。如果使用自己的地址，請註意下面的配置，根據自己的情況進行修改，不在累贅了。

鏡像版本號說明：

OK,這些鏡像下載完成就 OK 了，不會連外網的，就直接跳過吧。

主機配置

上面的內容下載好後，我們就可以安裝了。

更新系統

沒什麽可以介紹的。

yum update -y

安裝 Docker

K8S 的1.6.x 版本僅僅在 Docker 1.12上測試過，雖然最新版本 Docker 也可以運行，但是不推薦安裝最新版本，免得遇到什麽問題。

curl -sSL http://acs-public-mirror.oss-cn-hangzhou.aliyuncs.com/docker-engine/internet | sh /dev/stdin 1.12.6

安裝完成後，禁用 Docker 的更新，禁用方式為，在/etc/yum.conf添加

exclude=docker-engine*

配置 Docker

主要是配置一些加速器，避免自己下載鏡像速度太慢。

修改/etc/docker/daemon.json 添加如下內容：

{
"registry-mirrors": ["https://自己的加速地址"]
}

之後就是啟動Docker 的服務，

systemctl daemon-reload
systemctl enable docker
systemctl start docker

修改網絡

主要是開啟橋接相關支持，這個是 flannel 需要的配置，具體是否需要，看自己的網絡組件選擇的是什麽。

修改/usr/lib/sysctl.d/00-system.conf,將net.bridge.bridge-nf-call-iptables改成1.之後修改當前內核狀態

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

安裝K8S包

上傳RPM 包，到自己的服務器上，然後執行

yum install -y *.rpm

之後開啟kubelet的開機啟動

systemctl enable kubelet

然後配置 kubelet，修改/etc/systemd/system/kubelet.service.d/10-kubeadm.conf成如下文件

[Service]
Environment="KUBELET_KUBECONFIG_ARGS=--kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"
Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
Environment="KUBELET_DNS_ARGS=--cluster-dns=10.96.0.10 --cluster-domain=cluster.local"
Environment="KUBELET_AUTHZ_ARGS=--authorization-mode=Webhook --client-ca-file=/etc/kubernetes/pki/ca.crt"
Environment="KUBELET_ALIYUN_ARGS=--pod-infra-container-image=registry-vpc.cn-beijing.aliyuncs.com/bbt_k8s/pause-amd64:3.0"
ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_AUTHZ_ARGS $KUBELET_EXTRA_ARGS $KUBELET_ALIYUN_ARGS

在這裏主要修正2個問題，一個是將 POD 的基礎容器修改為我們自己源裏面的，另外一個是最新版本的 K8S 的資源管理和 Docker 默認的資源管理方式有沖突，這裏把這塊給刪除了。具體可以參考https://github.com/kubernetes/release/issues/306

然後重新 reload 服務。

systemctl daemon-reload

這樣就完成了主機環境的初始化，如果是使用虛擬機，拷貝3份就可以了。如果是實體機，3臺都按照這個步驟來一遍就好了。然後為每一臺主機根據類型設置好 HostName，K8S會把 HostName 當做主機標識。

啟動 Master

配置完主機後，我們就可以啟動我們的 Master 節點了，通常 Master 節點推薦2-3個，本地測試我們就簡單一些，一個節點就可以了。

export KUBE_REPO_PREFIX="registry-vpc.cn-beijing.aliyuncs.com/bbt_k8s"
export KUBE_ETCD_IMAGE="registry-vpc.cn-beijing.aliyuncs.com/bbt_k8s/etcd-amd64:3.0.17"
kubeadm init --kubernetes-version=v1.6.2 --pod-network-cidr=10.96.0.0/12

前面2個環境變量配置，是讓 kubeadm 初始化的時候，使用我們的鏡像源下載鏡像。

最後 kubeadm init 是初始化 Master 節點。其中需要配置的參數我說明一下。

執行完畢後，稍等一陣，就完成了。

kubeadm init --kubernetes-version=v1.6.2 --pod-network-cidr=10.96.0.0/12
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[init] Using Kubernetes version: v1.6.2
[init] Using Authorization mode: RBAC
[preflight] Running pre-flight checks
[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 [node0 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.61.41]
[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 14.583864 seconds
[apiclient] Waiting for at least one node to register
[apiclient] First node has registered after 6.008990 seconds
[token] Using token: e7986d.e440de5882342711
[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 1111.1111111111111 *.*.*.*:6443

安裝完成後，有一個內容非常重要，查看安裝日誌，拷貝類似於下面的語句，這條語句用來初始化之後的節點。

kubeadm join --token 11111.11111111111111 *.*.*.*:6443

接下來我們就可以去看看我們 K8S 的狀態。我這使用的是 Mac。 Linux 和 Windows 的同學自行處理。

安裝 kubectl

brew install kubectl

然後拷貝 Master 節點上的/etc/kubernetes/admin.conf文件到本機的~/.kube/config

之後執行kebectl get node。我這裏已經安裝完畢了，所以有全部信息，只要能看到節點，就算是成功了。

安裝網絡組件

接下來我們安裝網絡組件，我這裏使用的是flannel。創建2個文件

kube-flannel-rbac.yml

# Create the clusterrole and clusterrolebinding:
# $ kubectl create -f kube-flannel-rbac.yml
# Create the pod using the same namespace used by the flannel serviceaccount:
# $ kubectl create --namespace kube-system -f kube-flannel.yml
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: flannel
rules:
- apiGroups:
- ""
resources:
- pods
verbs:
- get
- apiGroups:
- ""
resources:
- nodes
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes/status
verbs:
- patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: flannel
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: flannel
subjects:
- kind: ServiceAccount
name: flannel
namespace: kube-system

kube-flannel-ds.yaml

---
apiVersion: v1
kind: ServiceAccount
metadata:
name: flannel
namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
name: kube-flannel-cfg
namespace: kube-system
labels:
tier: node
app: flannel
data:
cni-conf.json: |
{
"name": "cbr0",
"type": "flannel",
"delegate": {
"isDefaultGateway": true
}
}
net-conf.json: |
{
"Network": "10.96.0.0/12",
"Backend": {
"Type": "vxlan"
}
}
---
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
name: kube-flannel-ds
namespace: kube-system
labels:
tier: node
app: flannel
spec:
template:
metadata:
labels:
tier: node
app: flannel
spec:
hostNetwork: true
nodeSelector:
beta.kubernetes.io/arch: amd64
tolerations:
- key: node-role.kubernetes.io/master
operator: Exists
effect: NoSchedule
serviceAccountName: flannel
containers:
- name: kube-flannel
image: registry.cn-beijing.aliyuncs.com/bbt_k8s/flannel:v0.7.0-amd64
command: [ "/opt/bin/flanneld", "--ip-masq", "--kube-subnet-mgr" ]
securityContext:
privileged: true
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
volumeMounts:
- name: run
mountPath: /run
- name: flannel-cfg
mountPath: /etc/kube-flannel/
- name: install-cni
image: registry.cn-beijing.aliyuncs.com/bbt_k8s/flannel:v0.7.0-amd64
command: [ "/bin/sh", "-c", "set -e -x; cp -f /etc/kube-flannel/cni-conf.json /etc/cni/net.d/10-flannel.conf; while true; do sleep 3600; done" ]
volumeMounts:
- name: cni
mountPath: /etc/cni/net.d
- name: flannel-cfg
mountPath: /etc/kube-flannel/
volumes:
- name: run
hostPath:
path: /run
- name: cni
hostPath:
path: /etc/cni/net.d
- name: flannel-cfg
configMap:
name: kube-flannel-cfg

然後使用使用命令進行配置。

kubectl create -f kube-flannel-rbac.yml
kubectl create -f kube-flannel-ds.yaml

啟動 Node

分別在2個Node 節點,執行下面的命令。

export KUBE_REPO_PREFIX="registry-vpc.cn-beijing.aliyuncs.com/bbt_k8s"
export KUBE_ETCD_IMAGE="registry-vpc.cn-beijing.aliyuncs.com/bbt_k8s/etcd-amd64:3.0.17"
kubeadm join --token 1111.111111111111 *.*.*.*:6443

其中 kubeadm join 請參考啟動 Master 節點中的內容。

其它

理論上我們安裝到這裏，K8S 就已經可以使用了。接下來主要是K8S的 Dashboard 的安裝，僅供參考，不一定要安裝。

安裝 DashBoard 工具

創建文件kubernetes-dashboard.yaml

# Copyright 2015 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Configuration to deploy release version of the Dashboard UI compatible with
# Kubernetes 1.6 (RBAC enabled).
#
# Example usage: kubectl create -f <this_file>

apiVersion: v1
kind: ServiceAccount
metadata:
labels:
app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: kubernetes-dashboard
labels:
app: kubernetes-dashboard
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard
namespace: kube-system
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
labels:
app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
spec:
replicas: 1
revisionHistoryLimit: 10
selector:
matchLabels:
app: kubernetes-dashboard
template:
metadata:
labels:
app: kubernetes-dashboard
spec:
containers:
- name: kubernetes-dashboard
image: registry.cn-beijing.aliyuncs.com/bbt_k8s/kubernetes-dashboard-amd64:v1.6.0
imagePullPolicy: Always
ports:
- containerPort: 9090
protocol: TCP
args:
# Uncomment the following line to manually specify Kubernetes API server Host
# If not specified, Dashboard will attempt to auto discover the API server and connect
# to it. Uncomment only if the default does not work.
# - --apiserver-host=http://my-address:port
livenessProbe:
httpGet:
path: /
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
serviceAccountName: kubernetes-dashboard
# Comment the following tolerations if Dashboard must not be deployed on master
tolerations:
- key: node-role.kubernetes.io/master
effect: NoSchedule
---
kind: Service
apiVersion: v1
metadata:
labels:
app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
spec:
type: NodePort
ports:
- port: 80
targetPort: 9090
selector:
app: kubernetes-dashboard

創建文件dashboard-rbac.yaml

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

之後執行

kubectl create -f dashboard-rbac.yml
kubectl create -f kubernetes-dashboard.yaml

之後用下面的命令，獲取到對應端口號。主要是看 NodePort: <unset> 31867/TCP這樣的內容。然後使用http://NodeIp:NodePort訪問就可以了，其中 NodeIp 為 Master 或者 Node 的 IP，NodePort為NodePort的端口。

kubectl describe --namespace kube-system service kubernetes-dashboard

到此，這份安裝教程就到這裏結束了。最後奉上一份安裝後的截圖。

輕松加愉快的 Kubernetes 安裝教程