lvs+keepalived部署k8s v1.16.4高可用集群

一、部署环境

1.1 主机列表

主机名Centos版本ipdocker versionflannel versionKeepalived version主机配置备注
lvs-keepalived01 7.6.1810 172.27.34.28 / / v1.3.5 4C4G lvs-keepalived
lvs-keepalived01 7.6.1810 172.27.34.29 / / v1.3.5 4C4G lvs-keepalived
master01 7.6.1810 172.27.34.35 18.09.9 v0.11.0 / 4C4G control plane
master02 7.6.1810 172.27.34.36 18.09.9 v0.11.0 / 4C4G control plane
master03 7.6.1810 172.27.34.37 18.09.9 v0.11.0 / 4C4G control plane
work01 7.6.1810 172.27.34.161 18.09.9 / / 4C4G worker nodes
work02 7.6.1810 172.27.34.162 18.09.9 / / 4C4G worker nodes
work03 7.6.1810 172.27.34.163 18.09.9 / / 4C4G worker nodes
VIP 7.6.1810 172.27.34.222 / / v1.3.5 4C4G 在lvs-keepalived两台主机上浮动
client 7.6.1810 172.27.34.85 / / / 4C4G client

共有9台服务器,2台为lvs-keepalived集群,3台control plane集群,3台work集群,1台client。

1.2 k8s 版本

主机名kubelet versionkubeadm versionkubectl version备注
master01 v1.16.4 v1.16.4 v1.16.4 kubectl选装
master02 v1.16.4 v1.16.4 v1.16.4 kubectl选装
master03 v1.16.4 v1.16.4 v1.16.4 kubectl选装
work01 v1.16.4 v1.16.4 v1.16.4 kubectl选装
work02 v1.16.4 v1.16.4 v1.16.4 kubectl选装
work03 v1.16.4 v1.16.4 v1.16.4 kubectl选装
client / / v1.16.4 client

二、高可用架构

1. 架构图

本文采用kubeadm方式搭建高可用k8s集群,k8s集群的高可用实际是k8s各核心组件的高可用,这里使用集群模式(针对apiserver来讲),架构如下:

image-20200309100826283

2. 集群模式高可用架构说明

核心组件高可用模式高可用实现方式
apiserver 集群 lvs+keepalived
controller-manager 主备 leader election
scheduler 主备 leader election
etcd 集群 kubeadm
  • apiserver 通过lvs-keepalived实现高可用,vip将请求分发至各个control plane节点的apiserver组件;
  • controller-manager k8s内部通过选举方式产生领导者(由--leader-elect 选型控制,默认为true),同一时刻集群内只有一个controller-manager组件运行;
  • scheduler k8s内部通过选举方式产生领导者(由--leader-elect 选型控制,默认为true),同一时刻集群内只有一个scheduler组件运行;
  • etcd 通过运行kubeadm方式自动创建集群来实现高可用,部署的节点数为奇数,3节点方式最多容忍一台机器宕机。

三、Centos7.6安装

本文所有的服务器都为Centos7.6,Centos7.6安装详见:Centos7.6操作系统安装及优化全纪录

安装Centos时已经禁用了防火墙和selinux并设置了阿里源。

四、k8s集群安装准备工作

control plane和work节点都执行本部分操作,以master01为例记录搭建过程。

1. 配置主机名

1.1 修改主机名

[root@centos7 ~]# hostnamectl set-hostname master01
[root@centos7 ~]# more /etc/hostname             
master01

退出重新登陆即可显示新设置的主机名master01,各服务器修改为对应的主机名。

1.2 修改hosts文件

[root@master01 ~]# cat >> /etc/hosts << EOF
172.27.34.35    master01
172.27.34.36   master02
172.27.34.37    master03
172.27.34.161   work01 
172.27.34.162   work02
172.27.34.163   work03
EOF

image-20200309101133622

2. 验证mac地址uuid

[root@master01 ~]# cat /sys/class/net/ens160/address
[root@master01 ~]# cat /sys/class/dmi/id/product_uuid

image-20200309101255911

保证各节点mac和uuid唯一

3. 禁用swap

3.1 临时禁用

[root@master01 ~]# swapoff -a

3.2 永久禁用

若需要重启后也生效,在禁用swap后还需修改配置文件/etc/fstab,注释swap

[root@master01 ~]# sed -i.bak '/swap/s/^/#/' /etc/fstab

image-20200309101324503

4. 内核参数修改

本文的k8s网络使用flannel,该网络需要设置内核参数bridge-nf-call-iptables=1,修改这个参数需要系统有br_netfilter模块。

4.1 br_netfilter模块加载

查看br_netfilter模块:

[root@master01 ~]# lsmod |grep br_netfilter

如果系统没有br_netfilter模块则执行下面的新增命令,如有则忽略。

临时新增br_netfilter模块:

[root@master01 ~]# modprobe br_netfilter

该方式重启后会失效

永久新增br_netfilter模块:

[root@master01 ~]# cat > /etc/rc.sysinit << EOF
#!/bin/bash
for file in /etc/sysconfig/modules/*.modules ; do
[ -x $file ] && $file
done
EOF
[root@master01 ~]# cat > /etc/sysconfig/modules/br_netfilter.modules << EOF
modprobe br_netfilter
EOF
[root@master01 ~]# chmod 755 /etc/sysconfig/modules/br_netfilter.modules

image-20200309101351910

4.2 内核参数临时修改

[root@master01 ~]# sysctl net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-iptables = 1
[root@master01 ~]# sysctl net.bridge.bridge-nf-call-ip6tables=1
net.bridge.bridge-nf-call-ip6tables = 1

4.3 内核参数永久修改

[root@master01 ~]# cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
[root@master01 ~]# sysctl -p /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1

image-20200309101414595

5. 设置kubernetes源

5.1 新增kubernetes源

[root@master01 ~]# cat <<EOF > /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
  • [] 中括号中的是repository id,唯一,用来标识不同仓库
  • name 仓库名称,自定义
  • baseurl 仓库地址
  • enable 是否启用该仓库,默认为1表示启用
  • gpgcheck 是否验证从该仓库获得程序包的合法性,1为验证
  • repo_gpgcheck 是否验证元数据的合法性 元数据就是程序包列表,1为验证
  • gpgkey=URL 数字签名的公钥文件所在位置,如果gpgcheck值为1,此处就需要指定gpgkey文件的位置,如果gpgcheck值为0就不需要此项了

5.2 更新缓存

[root@master01 ~]# yum clean all
[root@master01 ~]# yum -y makecache

6. 免密登录

配置master01到master02、master03免密登录,本步骤只在master01上执行。

6.1 创建秘钥

[root@master01 ~]# ssh-keygen -t rsa

image-20200309101451722

6.2 将秘钥同步至master02/master03

[root@master01 ~]# ssh-copy-id -i /root/.ssh/id_rsa.pub root@172.27.34.35
[root@master01 ~]# ssh-copy-id -i /root/.ssh/id_rsa.pub root@172.27.34.36

image-20200309101519776

image-20200309101535664

6.3 免密登陆测试

[root@master01 ~]# ssh 172.27.34.36
[root@master01 ~]# ssh master03

image-20200309101612630

master01可以直接登录master02和master03,不需要输入密码。

7. 服务器重启

重启各control plane和work节点。

五、Docker安装

control plane和work节点都执行本部分操作。

1. 安装依赖包

[root@master01 ~]# yum install -y yum-utils   device-mapper-persistent-data   lvm2

image-20200309101722548

2. 设置Docker源

[root@master01 ~]# yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

image-20200309101850544

3. 安装Docker CE

3.1 docker安装版本查看

[root@master01 ~]# yum list docker-ce --showduplicates | sort -r

image-20200309162903305

3.2 安装docker

[root@master01 ~]# yum install docker-ce-18.09.9 docker-ce-cli-18.09.9 containerd.io -y

image-20200309162930299
指定安装的docker版本为18.09.9

4. 启动Docker

[root@master01 ~]# systemctl start docker
[root@master01 ~]# systemctl enable docker

image-20200309163022673

5. 命令补全

5.1 安装bash-completion

[root@master01 ~]# yum -y install bash-completion

5.2 加载bash-completion

[root@master01 ~]# source /etc/profile.d/bash_completion.sh

image-20200309163047803

6. 镜像加速

由于Docker Hub的服务器在国外,下载镜像会比较慢,可以配置镜像加速器。主要的加速器有:Docker官方提供的中国registry mirror、阿里云加速器、DaoCloud 加速器,本文以阿里加速器配置为例。

6.1 登陆阿里云容器模块

登陆地址为:https://cr.console.aliyun.com ,未注册的可以先注册阿里云账户

image-20200309163146167

6.2 配置镜像加速器

配置daemon.json文件

[root@master01 ~]# mkdir -p /etc/docker
[root@master01 ~]# tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://v16stybc.mirror.aliyuncs.com"]
}
EOF

重启服务

[root@master01 ~]# systemctl daemon-reload
[root@master01 ~]# systemctl restart docker

image-20200309163212089

加速器配置完成

7. 验证

[root@master01 ~]# docker --version
[root@master01 ~]# docker run hello-world

image-20200309163235352

通过查询docker版本和运行容器hello-world来验证docker是否安装成功。

8. 修改Cgroup Driver

8.1 修改daemon.json

修改daemon.json,新增‘"exec-opts": ["native.cgroupdriver=systemd"’

[root@master01 ~]# more /etc/docker/daemon.json 
{
  "registry-mirrors": ["https://v16stybc.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}

8.2 重新加载docker

[root@master01 ~]# systemctl daemon-reload
[root@master01 ~]# systemctl restart docker

修改cgroupdriver是为了消除告警:
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/

六、k8s安装

control plane和work节点都执行本部分操作

1. 版本查看

[root@master01 ~]# yum list kubelet --showduplicates | sort -r

image-20200309163328603

本文安装的kubelet版本是1.16.4,该版本支持的docker版本为1.13.1, 17.03, 17.06, 17.09, 18.06, 18.09。

2. 安装kubelet、kubeadm和kubectl

2.1 安装三个包

[root@master01 ~]# yum install -y kubelet-1.16.4 kubeadm-1.16.4 kubectl-1.16.4

image-20200309163354550

2.2 安装包说明

  • kubelet 运行在集群所有节点上,用于启动Pod和容器等对象的工具
  • kubeadm 用于初始化集群,启动集群的命令工具
  • kubectl 用于和集群通信的命令行,通过kubectl可以部署和管理应用,查看各种资源,创建、删除和更新各种组件

2.3 启动kubelet

启动kubelet并设置开机启动

[root@master01 ~]# systemctl enable kubelet && systemctl start kubelet

2.4 kubectl命令补全

[root@master01 ~]# echo "source <(kubectl completion bash)" >> ~/.bash_profile
[root@master01 ~]# source .bash_profile 

3. 下载镜像

3.1 镜像下载的脚本

Kubernetes几乎所有的安装组件和Docker镜像都放在goolge自己的网站上,直接访问可能会有网络问题,这里的解决办法是从阿里云镜像仓库下载镜像,拉取到本地以后改回默认的镜像tag。本文通过运行image.sh脚本方式拉取镜像。

[root@master01 ~]# more image.sh 
#!/bin/bash
url=registry.cn-hangzhou.aliyuncs.com/loong576
version=v1.16.4
images=(`kubeadm config images list --kubernetes-version=$version|awk -F '/' '{print $2}'`)
for imagename in ${images[@]} ; do
  docker pull $url/$imagename
  docker tag $url/$imagename k8s.gcr.io/$imagename
  docker rmi -f $url/$imagename
done

url为阿里云镜像仓库地址,version为安装的kubernetes版本。

3.2 下载镜像

运行脚本image.sh,下载指定版本的镜像

[root@master01 ~]# ./image.sh
[root@master01 ~]# docker images

image-20200309163431743

七、初始化Master

master01节点执行本部分操作。

1. kubeadm.conf

[root@master01 ~]# more kubeadm-config.yaml 
apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration
kubernetesVersion: v1.16.4
apiServer:
  certSANs:    #填写所有kube-apiserver节点的hostname、IP、VIP
  - master01
  - master02
  - master03
  - work01
  - work02
  - work03
  - 172.27.34.35
  - 172.27.34.36
  - 172.27.34.37
  - 172.27.34.161
  - 172.27.34.162
  - 172.27.34.163
  - 172.27.34.222
controlPlaneEndpoint: "172.27.34.222:6443"
networking:
  podSubnet: "10.244.0.0/16"

image-20200309163452682

kubeadm.conf为初始化的配置文件

2. master01起虚ip

在master01上起虚ip:172.27.34.222

[root@master01 ~]# ifconfig ens160:2 172.27.34.222 netmask 255.255.255.0 up

image-20200309163506636

起虚ip目的是为了执行master01的初始化,待初始化完成后去掉该虚ip

3. master初始化

[root@master01 ~]# kubeadm init --config=kubeadm-config.yaml

image-20200309163545663

记录kubeadm join的输出,后面需要这个命令将work节点和其他control plane节点加入集群中。

You can now join any number of control-plane nodes by copying certificate authorities 
and service account keys on each node and then running the following as root:

  kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2 \
    --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4 \
    --control-plane       

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2 \
    --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4 

初始化失败:

如果初始化失败,可执行kubeadm reset后重新初始化

[root@master01 ~]# kubeadm reset
[root@master01 ~]# rm -rf $HOME/.kube/config

image-20200309163604073

4. 加载环境变量

[root@master01 ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
[root@master01 ~]# source .bash_profile

本文所有操作都在root用户下执行,若为非root用户,则执行如下操作:

mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config

5. 安装flannel网络

在master01上新建flannel网络

[root@master01 ~]# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/2140ac876ef134e0ed5af15c65e414cf26827915/Documentation/kube-flannel.yml

image-20200309163624376

由于网络原因,可能会安装失败,可以在文末直接下载kube-flannel.yml文件,然后再执行apply

八、control plane节点加入k8s集群

1. 证书分发

1.1 master01分发证书

在master01上运行脚本cert-main-master.sh,将证书分发至master02和master03

[root@master01 ~]# ll|grep cert-main-master.sh 
-rwxr--r--  1 root root     638 1月  16 10:25 cert-main-master.sh
[root@master01 ~]# more cert-main-master.sh
USER=root # customizable
CONTROL_PLANE_IPS="172.27.34.36 172.27.34.37"
for host in ${CONTROL_PLANE_IPS}; do
    scp /etc/kubernetes/pki/ca.crt "${USER}"@$host:
    scp /etc/kubernetes/pki/ca.key "${USER}"@$host:
    scp /etc/kubernetes/pki/sa.key "${USER}"@$host:
    scp /etc/kubernetes/pki/sa.pub "${USER}"@$host:
    scp /etc/kubernetes/pki/front-proxy-ca.crt "${USER}"@$host:
    scp /etc/kubernetes/pki/front-proxy-ca.key "${USER}"@$host:
    scp /etc/kubernetes/pki/etcd/ca.crt "${USER}"@$host:etcd-ca.crt
    # Quote this line if you are using external etcd
    scp /etc/kubernetes/pki/etcd/ca.key "${USER}"@$host:etcd-ca.key
done

image-20200309163649608

1.2 master02移动证书至指定目录

在master02上运行脚本cert-other-master.sh,将证书移至指定目录

[root@master02 ~]# more cert-other-master.sh 
USER=root # customizable
mkdir -p /etc/kubernetes/pki/etcd
mv /${USER}/ca.crt /etc/kubernetes/pki/
mv /${USER}/ca.key /etc/kubernetes/pki/
mv /${USER}/sa.pub /etc/kubernetes/pki/
mv /${USER}/sa.key /etc/kubernetes/pki/
mv /${USER}/front-proxy-ca.crt /etc/kubernetes/pki/
mv /${USER}/front-proxy-ca.key /etc/kubernetes/pki/
mv /${USER}/etcd-ca.crt /etc/kubernetes/pki/etcd/ca.crt
# Quote this line if you are using external etcd
mv /${USER}/etcd-ca.key /etc/kubernetes/pki/etcd/ca.key
[root@master02 ~]# ./cert-other-master.sh 

image-20200309163710983

1.3 master03移动证书至指定目录

在master03上也运行脚本cert-other-master.sh

[root@master03 ~]# pwd
/root
[root@master03 ~]# ll|grep cert-other-master.sh 
-rwxr--r--  1 root root  484 1月  16 10:30 cert-other-master.sh
[root@master03 ~]# ./cert-other-master.sh 

2. master02加入k8s集群

[root@master03 ~]# kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2     --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4     --control-plane

运行初始化master生成的control plane节点加入集群的命令

image-20200309163732020

3. master03加入k8s集群

[root@master03 ~]# kubeadm join 172.27.34.222:6443 --token 0p7rzn.fdanprq4y8na36jh     --discovery-token-ca-cert-hash sha256:fc7a828208d554329645044633159e9dc46b0597daf66769988fee8f3fc0636b     --control-plane

image-20200309163754867

4. 加载环境变量

master02和master03加载环境变量

[root@master02 ~]# scp master01:/etc/kubernetes/admin.conf /etc/kubernetes/
[root@master02 ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
[root@master02 ~]# source .bash_profile 
[root@master03 ~]# scp master01:/etc/kubernetes/admin.conf /etc/kubernetes/
[root@master03 ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
[root@master03 ~]# source .bash_profile 

image-20200309163807751

该步操作是为了在master02和master03上也能执行kubectl命令。

5. k8s集群节点查看

[root@master01 ~]# kubectl get nodes
[root@master01 ~]# kubectl get po -o wide -n kube-system 

image-20200309163832464发现master01和master03下载flannel异常,分别在master01和master03上手动下载该镜像后正常。

[root@master01 ~]# docker pull  registry.cn-hangzhou.aliyuncs.com/loong576/flannel:v0.11.0-amd64
[root@master03 ~]# docker pull  registry.cn-hangzhou.aliyuncs.com/loong576/flannel:v0.11.0-amd64

image-20200309163932412

九、work节点加入k8s集群

1. work01加入k8s集群

[root@work01 ~]# kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2     --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4

运行初始化master生成的work节点加入集群的命令

image-20200309163954129

2. work02加入k8s集群

[root@work02 ~]# kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2     --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4

image-20200309164016933

3. work03加入k8s集群

[root@work03 ~]# kubeadm join 172.27.34.222:6443 --token lw90fv.j1lease5jhzj9ih2     --discovery-token-ca-cert-hash sha256:79575e7a39eac086e121364f79e58a33f9c9de2a4e9162ad81d0abd1958b24f4

image-20200309164037410

4. k8s集群各节点查看

[root@master01 ~]# kubectl get nodes
[root@master01 ~]# kubectl get po -o wide -n kube-system 

image-20200309164055268

十、ipvs安装

lvs-keepalived01和lvs-keepalived02都执行本操作。

1. 安装ipvs

LVS无需安装,安装的是管理工具,第一种叫ipvsadm,第二种叫keepalive。ipvsadm是通过命令行管理,而keepalive读取配置文件管理。

[root@lvs-keepalived01 ~]# yum -y install ipvsadm

image-20200309164149554

2. 加载ipvsadm模块

把ipvsadm模块加载进系统

[root@lvs-keepalived01 ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
[root@lvs-keepalived01 ~]# lsmod | grep ip_vs
ip_vs                 145497  0 
nf_conntrack          133095  1 ip_vs
libcrc32c              12644  3 xfs,ip_vs,nf_conntrack

image-20200309164204749

lvs相关实践详见:LVS+Keepalived+Nginx负载均衡搭建测试

十一、keepalived安装

lvs-keepalived01和lvs-keepalived02都执行本操作。

1. keepalived安装

[root@lvs-keepalived01 ~]# yum -y install keepalived

image-20200309164222695

2. keepalived配置

lvs-keepalived01配置如下:

[root@lvs-keepalived01 ~]# more /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
   router_id lvs-keepalived01   #router_id 机器标识,通常为hostname,但不一定非得是hostname。故障发生时,邮件通知会用到。
}
vrrp_instance VI_1 {            #vrrp实例定义部分
    state MASTER                #设置lvs的状态,MASTER和BACKUP两种,必须大写 
    interface ens160            #设置对外服务的接口
    virtual_router_id 100       #设置虚拟路由标示,这个标示是一个数字,同一个vrrp实例使用唯一标示 
    priority 100                #定义优先级,数字越大优先级越高,在一个vrrp——instance下,master的优先级必须大于backup
    advert_int 1                #设定master与backup负载均衡器之间同步检查的时间间隔,单位是秒
    authentication {            #设置验证类型和密码
        auth_type PASS          #主要有PASS和AH两种
        auth_pass 1111          #验证密码,同一个vrrp_instance下MASTER和BACKUP密码必须相同
    }
    virtual_ipaddress {         #设置虚拟ip地址,可以设置多个,每行一个
        172.27.34.222
    }
}
virtual_server 172.27.34.222 6443 {  #设置虚拟服务器,需要指定虚拟ip和服务端口
    delay_loop 6                     #健康检查时间间隔
    lb_algo wrr                      #负载均衡调度算法
    lb_kind DR                       #负载均衡转发规则
    #persistence_timeout 50          #设置会话保持时间,对动态网页非常有用
    protocol TCP                     #指定转发协议类型,有TCP和UDP两种
    real_server 172.27.34.35 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
    real_server 172.27.34.36 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
    real_server 172.27.34.37 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
}

lvs-keepalived02配置如下:

[root@lvs-keepalived02 ~]# more /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
   router_id lvs-keepalived02   #router_id 机器标识,通常为hostname,但不一定非得是hostname。故障发生时,邮件通知会用到。
}
vrrp_instance VI_1 {            #vrrp实例定义部分
    state BACKUP                #设置lvs的状态,MASTER和BACKUP两种,必须大写 
    interface ens160            #设置对外服务的接口
    virtual_router_id 100       #设置虚拟路由标示,这个标示是一个数字,同一个vrrp实例使用唯一标示 
    priority 90                 #定义优先级,数字越大优先级越高,在一个vrrp——instance下,master的优先级必须大于backup
    advert_int 1                #设定master与backup负载均衡器之间同步检查的时间间隔,单位是秒
    authentication {            #设置验证类型和密码
        auth_type PASS          #主要有PASS和AH两种
        auth_pass 1111          #验证密码,同一个vrrp_instance下MASTER和BACKUP密码必须相同
    }
    virtual_ipaddress {         #设置虚拟ip地址,可以设置多个,每行一个
        172.27.34.222
    }
}
virtual_server 172.27.34.222 6443 {  #设置虚拟服务器,需要指定虚拟ip和服务端口
    delay_loop 6                     #健康检查时间间隔
    lb_algo wrr                      #负载均衡调度算法
    lb_kind DR                       #负载均衡转发规则
    #persistence_timeout 50          #设置会话保持时间,对动态网页非常有用
    protocol TCP                     #指定转发协议类型,有TCP和UDP两种
    real_server 172.27.34.35 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
    real_server 172.27.34.36 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
    real_server 172.27.34.37 6443 {  #配置服务器节点1,需要指定real server的真实IP地址和端口
    weight 10                        #设置权重,数字越大权重越高
    TCP_CHECK {                      #realserver的状态监测设置部分单位秒
       connect_timeout 10            #连接超时为10秒
       retry 3                       #重连次数
       delay_before_retry 3          #重试间隔
       connect_port 6443             #连接端口为6443,要和上面的保持一致
       }
    }
}

3. master01上去掉vip

[root@master01 ~]# ifconfig ens160:2 172.27.34.222 netmask 255.255.255.0 down

image-20200309164245783

master01上去掉初始化使用的ip 172.27.34.222

4. 启动keepalived

lvs-keepalived01和lvs-keepalived02都启动keepalived并设置为开机启动

[root@lvs-keepalived01 ~]# service keepalived start
Redirecting to /bin/systemctl start keepalived.service
[root@lvs-keepalived01 ~]# systemctl enable keepalived
Created symlink from /etc/systemd/system/multi-user.target.wants/keepalived.service to /usr/lib/systemd/system/keepalived.service.

5. vip查看

[root@lvs-keepalived01 ~]# ip a

image-20200309164434474

此时vip在lvs-keepalived01上

十二、control plane节点配置

control plane都执行本操作。

1. 新建realserver.sh

打开control plane所在服务器的“路由”功能、关闭“ARP查询”功能并设置回环ip,三台control plane配置相同,如下:

[root@master01 ~]# cd /etc/rc.d/init.d/
[root@master01 init.d]# more realserver.sh 
#!/bin/bash
    SNS_VIP=172.27.34.222
    case "$1" in
    start)
        ifconfig lo:0 $SNS_VIP netmask 255.255.255.255 broadcast $SNS_VIP
        /sbin/route add -host $SNS_VIP dev lo:0
        echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
        echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
        echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
        echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
        sysctl -p >/dev/null 2>&1
        echo "RealServer Start OK"
        ;;
    stop)
        ifconfig lo:0 down
        route del $SNS_VIP >/dev/null 2>&1
        echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
        echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
        echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
        echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
        echo "RealServer Stoped"
        ;;
    *)
        echo "Usage: $0 {start|stop}"
        exit 1
    esac
    exit 0

此脚本用于control plane节点绑定 VIP ,并抑制响应 VIP 的 ARP 请求。这样做的目的是为了不让关于 VIP 的 ARP 广播时,节点服务器应答( 因为control plane节点都绑定了 VIP ,如果不做设置它们会应答,就会乱套 )。

2 运行realserver.sh脚本

在所有control plane节点执行realserver.sh脚本:

[root@master01 init.d]# chmod u+x realserver.sh 
[root@master01 init.d]# /etc/rc.d/init.d/realserver.sh start
RealServer Start OK

给realserver.sh脚本授予执行权限并运行realserver.sh脚本

image-20200309164522352

3. realserver.sh开启启动

[root@master01 init.d]# sed -i '$a /etc/rc.d/init.d/realserver.sh start' /etc/rc.d/rc.local
[root@master01 init.d]# chmod u+x /etc/rc.d/rc.local 

十三、client配置

1. 设置kubernetes源

1.1 新增kubernetes源

[root@client ~]# cat <<EOF > /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

image-20200309164547306

1.2 更新缓存

[root@client ~]# yum clean all
[root@client ~]# yum -y makecache

2. 安装kubectl

[root@client ~]# yum install -y kubectl-1.16.4

image-20200309164607902

安装版本与集群版本保持一致

3. 命令补全

3.1 安装bash-completion

[root@client ~]# yum -y install bash-completion

3.2 加载bash-completion

[root@client ~]# source /etc/profile.d/bash_completion.sh

image-20200309164627949

3.3 拷贝admin.conf

[root@client ~]# mkdir -p /etc/kubernetes
[root@client ~]# scp 172.27.34.35:/etc/kubernetes/admin.conf /etc/kubernetes/
[root@client ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
[root@client ~]# source .bash_profile 

3.4 加载环境变量

[root@master01 ~]# echo "source <(kubectl completion bash)" >> ~/.bash_profile
[root@master01 ~]# source .bash_profile 

4. kubectl测试

[root@client ~]# kubectl get nodes 
[root@client ~]# kubectl get cs
[root@client ~]# kubectl cluster-info 
[root@client ~]# kubectl get po -o wide -n kube-system 

image-20200309164648821

十四、Dashboard搭建

本节内容都在client节点完成。

1. 下载yaml

[root@client ~]# wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta8/aio/deploy/recommended.yaml

如果连接超时,可以多试几次。recommended.yaml已上传,也可以在文末下载。

2. 配置yaml

2.1 修改镜像地址

[root@client ~]# sed -i 's/kubernetesui/registry.cn-hangzhou.aliyuncs.com\/loong576/g' recommended.yaml

由于默认的镜像仓库网络访问不通,故改成阿里镜像

2.2 外网访问

[root@client ~]# sed -i '/targetPort: 8443/a\ \ \ \ \ \ nodePort: 30001\n\ \ type: NodePort' recommended.yaml

配置NodePort,外部通过https://NodeIp:NodePort 访问Dashboard,此时端口为30001

2.3 新增管理员帐号

[root@client ~]# cat >> recommended.yaml << EOF
---
# ------------------- dashboard-admin ------------------- #
apiVersion: v1
kind: ServiceAccount
metadata:
  name: dashboard-admin
  namespace: kubernetes-dashboard

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

image-20200309164711264

创建超级管理员的账号用于登录Dashboard

3. 部署访问

3.1 部署Dashboard

[root@client ~]# kubectl apply -f recommended.yaml

image-20200309164726665

3.2 状态查看

[root@client ~]# kubectl get all -n kubernetes-dashboard 

image-20200309164751965

3.3 令牌查看

[root@client ~]# kubectl describe secrets -n kubernetes-dashboard dashboard-admin

image-20200309164805099
令牌为:

eyJhbGciOiJSUzI1NiIsImtpZCI6Ii1SOU1pNGswQnJCVUtCaks2TlBnMGxUdGRSdTlPS0s0MjNjUkdlNzFRVXMifQ.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.WJPzxkAGYjtq556d3HuXNh6g0sDYm2h6U_FsPDvvfhquYSccPGJ1UzX-lKxhPYyCegc603D7yFCc9zQOzpONttkue3rGdOz8KePOAHCUX7Xp_yTcJg15BPxQDDny6Lebu0fFXh_fpbU2_35nG28lRjiwKG3mV3O5uHdX5nk500RBmLkw3F054ww66hgFBfTH2HVDi1jOlAKWC0xatdxuqp2JkMqiBCZ_8Zwhi66EQYAMT1xu8Sn5-ur_6QsgaNNYhCeNxqHUiEFIZdLNu8QAnsKJJuhxxXd2KhIF6dwMvvOPG1djKCKSyNRn-SGILDucu1_6FoBG1DiNcIr90cPAtA

3.4 访问

请使用火狐浏览器访问:https://control plane ip:30001,即https://172.27.34.35/36/37:30001/
image-20200309164825977

image-20200309164846452

接受风险
image-20200309164906305
通过令牌方式登录
image-20200309164924294

登录的首页显示

image-20200309164937984

切换到命名空间kubernetes-dashboard,查看资源。

Dashboard提供了可以实现集群管理、工作负载、服务发现和负载均衡、存储、字典配置、日志视图等功能。

为了丰富dashboard的统计数据和图表,可以安装heapster组件。heapster组件实践详见:k8s实践(十一):heapster+influxdb+grafana实现kubernetes集群监

十五、k8s集群高可用测试

1. 组件所在节点查看

通过ipvsadm查看apiserver所在节点,通过leader-elect查看scheduler和controller-manager所在节点:

1.1 apiserver节点查看

在lvs-keepalived01上执行ipvsadm查看apiserver转发到的服务器

[root@lvs-keepalived01 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.35:6443            Route   10     2          0         
  -> 172.27.34.36:6443            Route   10     2          0         
  -> 172.27.34.37:6443            Route   10     2          0  

image-20200309165006437

1.2 controller-manager和scheduler节点查看

在client节点上查看controller-manager和scheduler组件所在节点

[root@client ~]# kubectl get endpoints kube-controller-manager -n kube-system -o yaml |grep holderIdentity
    control-plane.alpha.kubernetes.io/leader: '{"holderIdentity":"master01_0a2bcea9-d17e-405b-8b28-5059ca434144","leaseDurationSeconds":15,"acquireTime":"2020-01-19T03:07:51Z","renewTime":"2020-01-19T04:40:20Z","leaderTransitions":2}'
[root@client ~]# kubectl get endpoints kube-scheduler -n kube-system -o yaml |grep holderIdentity
    control-plane.alpha.kubernetes.io/leader: '{"holderIdentity":"master01_c284cee8-57cf-46e7-a578-6c0a10aedb37","leaseDurationSeconds":15,"acquireTime":"2020-01-19T03:07:51Z","renewTime":"2020-01-19T04:40:30Z","leaderTransitions":2}'

image-20200309165022245

组件名所在节点
apiserver master01、master02、master03
controller-manager master01
scheduler master01

2. master01关机

2.1 关闭master01

关闭master01,模拟宕机

[root@master01 ~]# init 0

2.2 apiserver组件节点查看

lvs-keepalived01上查看apiserver节点链接情况

[root@lvs-keepalived01 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.36:6443            Route   10     4          0         
  -> 172.27.34.37:6443            Route   10     2          0 

image-20200309165043615

发现master01的apiserver被移除集群,即访问172.27.34.222:64443时不会被调度到master01

2.3 controller-manager和scheduler组件节点查看

client节点上再次运行查看controller-manager和scheduler命令

[root@client ~]# kubectl get endpoints kube-controller-manager -n kube-system -o yaml |grep holderIdentity
    control-plane.alpha.kubernetes.io/leader: '{"holderIdentity":"master03_9481b109-f236-432a-a2cb-8d0c27417396","leaseDurationSeconds":15,"acquireTime":"2020-01-19T04:42:22Z","renewTime":"2020-01-19T04:45:45Z","leaderTransitions":3}'
[root@client ~]# kubectl get endpoints kube-scheduler -n kube-system -o yaml |grep holderIdentity
    control-plane.alpha.kubernetes.io/leader: '{"holderIdentity":"master03_6d84981b-3ab9-4a00-a86a-47bd2f5c7729","leaseDurationSeconds":15,"acquireTime":"2020-01-19T04:42:23Z","renewTime":"2020-01-19T04:45:48Z","leaderTransitions":3}'
[root@client ~]# 

image-20200309165106862

controller-manager和scheduler都被切换到master03节点

组件名所在节点
apiserver master02、master03
controller-manager master03
scheduler master03

2.4 集群功能性测试

所有功能性测试都在client节点完成。

2.4.1 查询

[root@client ~]# kubectl get nodes
NAME       STATUS     ROLES    AGE   VERSION
master01   NotReady   master   22h   v1.16.4
master02   Ready      master   22h   v1.16.4
master03   Ready      master   22h   v1.16.4
work01     Ready      <none>   22h   v1.16.4
work02     Ready      <none>   22h   v1.16.4
work03     Ready      <none>   22h   v1.16.4

image-20200309165121411

master01状态为NotReady

2.4.2 新建pod

[root@client ~]# more nginx-master.yaml 
apiVersion: apps/v1             #描述文件遵循extensions/v1beta1版本的Kubernetes API
kind: Deployment                #创建资源类型为Deployment
metadata:                       #该资源元数据
  name: nginx-master            #Deployment名称
spec:                           #Deployment的规格说明
  selector:
    matchLabels:
      app: nginx 
  replicas: 3                   #指定副本数为3
  template:                     #定义Pod的模板
    metadata:                   #定义Pod的元数据
      labels:                   #定义label(标签)
        app: nginx              #label的key和value分别为app和nginx
    spec:                       #Pod的规格说明
      containers:               
      - name: nginx             #容器的名称
        image: nginx:latest     #创建容器所使用的镜像
[root@client ~]# kubectl apply -f nginx-master.yaml 
deployment.apps/nginx-master created
[root@client ~]# kubectl get po -o wide
NAME                            READY   STATUS    RESTARTS   AGE   IP           NODE     NOMINATED NODE   READINESS GATES
nginx-master-75b7bfdb6b-9d66p   1/1     Running   0          20s   10.244.3.6   work01   <none>           <none>
nginx-master-75b7bfdb6b-h4bql   1/1     Running   0          20s   10.244.5.5   work03   <none>           <none>
nginx-master-75b7bfdb6b-zmc68   1/1     Running   0          20s   10.244.4.5   work02   <none>           <none>

image-20200309165142390

以新建pod nginx为例测试集群是否能正常对外提供服务。

2.5 结论

在3节点的k8s集群中,当有一个control plane节点宕机时,集群各项功能不受影响。

3. master02关机

在master01处于关闭状态下,继续关闭master02,测试集群还能否正常对外服务。

3.1 关闭master02

[root@master02 ~]# init 0

3.2 apiserver组件节点查看

[root@lvs-keepalived01 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.37:6443            Route   10     6          20 

image-20200309165159752

此时对集群的访问都转到master03

3.3 集群功能测试

[root@client ~]# kubectl get nodes
The connection to the server 172.27.34.222:6443 was refused - did you specify the right host or port?

3.4 结论

在3节点的k8s集群中,当有两个control plane节点同时宕机时,etcd集群崩溃,整个k8s集群也不能正常对外服务。

十六、lvs-keepalived集群高可用测试

1. 高可用测试前检查

1.1 k8s集群检查

[root@client ~]# kubectl get nodes
NAME       STATUS   ROLES    AGE    VERSION
master01   Ready    master   161m   v1.16.4
master02   Ready    master   144m   v1.16.4
master03   Ready    master   142m   v1.16.4
work01     Ready    <none>   137m   v1.16.4
work02     Ready    <none>   135m   v1.16.4
work03     Ready    <none>   134m   v1.16.4

集群内个节点运行正常

1.2 vip查看

[root@lvs-keepalived01 ~]# ip a|grep 222
    inet 172.27.34.222/32 scope global ens160

发现vip运行在lvs-keepalived01上

1.3 链接情况

lvs-keepalived01:

[root@lvs-keepalived01 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.35:6443            Route   10     6          0         
  -> 172.27.34.36:6443            Route   10     0          0         
  -> 172.27.34.37:6443            Route   10     38         0  

lvs-keepalived02:

[root@lvs-keepalived02 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.35:6443            Route   10     0          0         
  -> 172.27.34.36:6443            Route   10     0          0         
  -> 172.27.34.37:6443            Route   10     0          0  

2. lvs-keepalived01关机

关闭lvs-keepalived01,模拟宕机

[root@lvs-keepalived01 ~]# init 0

2.1 k8s集群检查

[root@client ~]# kubectl get nodes
NAME       STATUS   ROLES    AGE    VERSION
master01   Ready    master   166m   v1.16.4
master02   Ready    master   148m   v1.16.4
master03   Ready    master   146m   v1.16.4
work01     Ready    <none>   141m   v1.16.4
work02     Ready    <none>   139m   v1.16.4
work03     Ready    <none>   138m   v1.16.4

集群内个节点运行正常

2.2 vip查看

[root@lvs-keepalived02 ~]# ip a|grep 222
    inet 172.27.34.222/32 scope global ens160

发现vip已漂移至lvs-keepalived02

2.3 链接情况

lvs-keepalived02:

[root@lvs-keepalived02 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.27.34.222:6443 wrr
  -> 172.27.34.35:6443            Route   10     1          0         
  -> 172.27.34.36:6443            Route   10     4          0         
  -> 172.27.34.37:6443            Route   10     1          0  

2.4 集群功能性测试

[root@client ~]# kubectl delete -f nginx-master.yaml 
deployment.apps "nginx-master" deleted
[root@client ~]# kubectl get po -o wide
NAME                            READY   STATUS        RESTARTS   AGE   IP           NODE     NOMINATED NODE   READINESS GATES
nginx-master-75b7bfdb6b-9d66p   0/1     Terminating   0          20m   10.244.3.6   work01   <none>           <none>
nginx-master-75b7bfdb6b-h4bql   0/1     Terminating   0          20m   10.244.5.5   work03   <none>           <none>
nginx-master-75b7bfdb6b-zmc68   0/1     Terminating   0          20m   10.244.4.5   work02   <none>           <none>
[root@client ~]# kubectl get po -o wide
No resources found in default namespace.

image-20200309165304669

删除之前新建的pod nginx,成功删除。

2.5 结论

当lvs-keepalived集群有一台宕机时,对k8s集群无影响,仍能正常对外提供服务。

本文所有脚本和配置文件已上传github:lvs-keepalived-install-k8s-HA-cluster

单机版k8s集群部署详见:k8s实践(一):Centos7.6部署k8s(v1.14.2)集群

主备高可用版k8s集群部署详见:k8s实践(十五):Centos7.6部署k8s v1.16.4高可用集群(主备模式)

image-20200309002139092

posted @ 2020-04-30 15:06  老虎逛大街  阅读(631)  评论(0编辑  收藏  举报
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