Kubernetes安装部署流程
Kubernetes 介绍
Kubernetes是当今最流行的开源容器管理平台，它就是大名鼎鼎的Google Borg的开源版本。Google在2014年推出了Kubernetes。
Kubernetes源于希腊语，意为舵手，K8S是一个简称，因为首尾字母中间正好有8个字母。基于容器技术，Kubernetes可以方便的进行集群应用的部署、扩容、缩容、自愈机制、服务发现、负载均衡、日志、监控等功能，大大减少日常运维的工作量。
Kubernetes所有的操作都可以通过Kubernetes API来进行，通过API来操作Kubernetes中的对象，包括Pod、Service、Volume、Namespace等等。
Kubernetes 设计架构
安装前准备
- 一台或多台机器，操作系统CentOS7.x86_x64
- 硬件配置：2GB或更多RAM，2个CPU或更多CPU，硬盘30GB或更多
- 集群中所有机器之间网络互通
- 可以访问外网，需要拉取镜像
- 禁止swap分区
1.准备环境
分别在master、node1、node2（执行）
关闭防火墙
$ systemctl stop firewalld
$ systemctl disable firewalld
关闭swap
$ swapoff -a $ 临时
$ vim /etc/fstab $ 永久
添加主机名与IP对应关系
192.168.31.140 k8s-master
192.168.31.141 k8s-node1
192.168.31.142 k8s-node2
将桥连的IPv4流量传递到iptables的链中：
$ cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge.-nf-call-ip6tables = 1
net.bridge.bridge.-nf-call-iptables = 1
EOF2.安装Docker
分别在master、node1、node2（安装docker）
$ wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
$ yum -y install docker-ce-18.06.1.ce-3.el7
$ systemctl enable docker && systemctl start docker
$ docker --version3.添加阿里云YUM软件源
分别在master、node1、node2（执行）
$ cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF4.安装kubeadm、kubelet、kubectl
分别在master、node1、node2（执行）
$ yum -y install kubelet-1.15.0 kubeadm-1.15.0 kubectl-1.15.0
$ systemctl enable kubelet.service部署kubernetes Master
1.在192.168.31.140（Master）执行，由于默认拉取的镜像文件地址是国内无法下载的，因此指定阿里云镜像地址。
$ kubeadm init \
--apiserver-advertise-address=192.168.31.140 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.15.0 \
--service-cidr=10.1.0.0/16 \
--pod-network-cidr=10.244.0.0/16$ mkdir -p $HOME/.kube
$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
$ sudo chown $(id -u):$(id -g) $HOME/.kube/config2.下载kube-flannel.yml官方文件，现在国内下载不了该站点的文件，可以通过修改hosts文件的方法解决，找到真实IP地址并添加到hosts文件的最后一行。
$ 199.232.68.133 raw.githubusercontent.com >> /etc/hosts
$ kubectl apply -f
https://raw.githubusercontent.com/coreos/flannel/a70459be0084506e4ec919aa1c114638878db11b/Documentation/kube-flannel.yml
3.分别在master、node1、node2上拉取镜像flannel:v0.11.0-amd64
$ docker pull lizhenliang/flannel:v0.11.0-amd64
有时候会网速慢下载不下来，但别的机器有镜像时，可以在一台机器中复制镜像到别的机器上。
查看所有镜像文件
$ docker images
压缩镜像
$ docker save -o v0.11.0-flannel.tar quay.io/coreos/flannel
在另一台机器上解压镜像
docker load < v0.11.0-flannel.tar
安装flannel
$ kubectl apply -f kube-flannel.yml4.安装节点到master上,复制初始化中打印的命令并分别在node1和node2上执行
$ kubeadm join 192.168.31.140:6443 --token 78yk4x.yk07bitlne6z08uh --discovery-token-ca-cert-hash sha256:f3d660ab28b0278eb3679b7fb63fedd673d37a6e43a060b18080fc80c7a0ab225.当镜像拉取成功后会有如图所示的提示信息
6.执行命令可看到节点信息已准备就绪
$ kubectl get nodes
部署kubernetes-dashboard
1.下载UI镜像
$ docker pull lizhenliang/kubernetes-dashboard-amd64:v1.10.12.修改kubernetes-dashboard.yaml配置
# Copyright 2017 The Kubernetes Authors.
#
# 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 1.8.
#
# Example usage: kubectl create -f
# ------------------- Dashboard Secret ------------------- #
apiVersion: v1
kind: Secret
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard-certs
namespace: kube-system
type: Opaque
---
# ------------------- Dashboard Service Account ------------------- #
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
---
# ------------------- Dashboard Role & Role Binding ------------------- #
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: kubernetes-dashboard-minimal
namespace: kube-system
rules:
# Allow Dashboard to create 'kubernetes-dashboard-key-holder' secret.
- apiGroups: [""]
resources: ["secrets"]
verbs: ["create"]
# Allow Dashboard to create 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
resources: ["configmaps"]
verbs: ["create"]
# Allow Dashboard to get, update and delete Dashboard exclusive secrets.
- apiGroups: [""]
resources: ["secrets"]
resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs"]
verbs: ["get", "update", "delete"]
# Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
resources: ["configmaps"]
resourceNames: ["kubernetes-dashboard-settings"]
verbs: ["get", "update"]
# Allow Dashboard to get metrics from heapster.
- apiGroups: [""]
resources: ["services"]
resourceNames: ["heapster"]
verbs: ["proxy"]
- apiGroups: [""]
resources: ["services/proxy"]
resourceNames: ["heapster", "http:heapster:", "https:heapster:"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: kubernetes-dashboard-minimal
namespace: kube-system
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: kubernetes-dashboard-minimal
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard
namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: kubernetes-dashboard
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard
namespace: kube-system
roleRef:
kind: ClusterRole
name: cluster-admin
apiGroup: rbac.authorization.k8s.io
---
# ------------------- Dashboard Deployment ------------------- #
kind: Deployment
apiVersion: apps/v1beta2
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
spec:
replicas: 1
revisionHistoryLimit: 10
selector:
matchLabels:
k8s-app: kubernetes-dashboard
template:
metadata:
labels:
k8s-app: kubernetes-dashboard
spec:
serviceAccountName: kubernetes-dashboard-admin
containers:
- name: kubernetes-dashboard
image: lizhenliang/kubernetes-dashboard-amd64:v1.10.1
ports:
- containerPort: 9090
protocol: TCP
args:
#- --auto-generate-certificates
# 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://10.0.1.168:8080
volumeMounts:
- name: kubernetes-dashboard-certs
mountPath: /certs
# Create on-disk volume to store exec logs
- mountPath: /tmp
name: tmp-volume
livenessProbe:
httpGet:
scheme: HTTP
path: /
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
volumes:
- name: kubernetes-dashboard-certs
secret:
secretName: kubernetes-dashboard-certs
- name: tmp-volume
emptyDir: {}
serviceAccountName: kubernetes-dashboard
# Comment the following tolerations if Dashboard must not be deployed on master
tolerations:
- key: node-role.kubernetes.io/master
effect: NoSchedule
---
# ------------------- Dashboard Service ------------------- #
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kube-system
spec:
ports:
- port: 9090
targetPort: 9090
selector:
k8s-app: kubernetes-dashboard
# ------------------------------------------------------------
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard-external
namespace: kube-system
spec:
ports:
- port: 9090
targetPort: 9090
nodePort: 30090
type: NodePort
selector:
k8s-app: kubernetes-dashboard 3.安装配置
$ kubectl apply -f kubernetes-dashboard.yaml4.查看pod service列表
$ kubectl get pods,svc -n kube-system
5.输入IP:30090显示UI界面
