K8S集群（高可用）搭建详细过程

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多master（高可用）

K8S集群（高可用）搭建详细过程_docker

1. 安装要求

在开始之前，部署Kubernetes集群机器需要满足以下几个条件：

一台或多台机器，操作系统
硬件配置：2GB或更多RAM，2个CPU或更多CPU，硬盘30GB或更多
可以访问外网，需要拉取镜像，如果服务器不能上网，需要提前下载镜像并导入节点
禁止swap分区

2. 准备环境（所有节点操作）

角色	IP
VIP（虚拟ip）	192.168.169.50
k8s-master1	192.168.169.51
k8s-master2	192.168.169.52
k8s-node1	192.168.169.53
k8s-node2	192.168.169.54

# 关闭防火墙

systemctl stop firewalld

systemctl disable firewalld

# 关闭selinux

sed -i 's/enforcing/disabled/' /etc/selinux/config # 永久

setenforce 0 # 临时

# 关闭swap

swapoff -a # 临时

sed -ri 's/.*swap.*/#&/' /etc/fstab # 永久

# 根据规划设置主机名

hostnamectl set-hostname <hostname>

# 在master添加hosts

K8S集群（高可用）搭建详细过程_docker_02

# 将桥接的IPv4流量传递到iptables的链

K8S集群（高可用）搭建详细过程_docker_03

sysctl --system # 生效

# 时间同步

yum install ntpdate -y

ntpdate time.windows.com

3. 所有master节点部署keepalived

3.1 安装相关包和keepalived

yum install -y conntrack-tools libseccomp libtool-ltdl

yum install -y keepalived

3.2配置master节点

master1节点配置

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id k8s
}

vrrp_script check_haproxy {
    script "killall -0 haproxy"
    interval 3
    weight -2
    fall 10
    rise 2
}

vrrp_instance VI_1 {
    state MASTER
    interface ens33
    virtual_router_id 51
    priority 250
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass ceb1b3ec013d66163d6ab
    }
    virtual_ipaddress {
        192.168.169.50
    }
    track_script {
        check_haproxy
    }
}

master2节点配置

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id k8s
}

vrrp_script check_haproxy {
    script "killall -0 haproxy"
    interval 3
    weight -2
    fall 10
    rise 2
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 200
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass ceb1b3ec013d66163d6ab
    }
    virtual_ipaddress {
        192.168.169.50
    }
    track_script {
        check_haproxy
    }
}

3.3 启动和检查

在两台master节点都执行

# 启动keepalived

$ systemctl start keepalived.service

设置开机启动

$ systemctl enable keepalived.service

# 查看启动状态

$ systemctl status keepalived.service

启动后查看master1的网卡信息

ip a s ens33

4. 部署haproxy

4.1 安装

yum install -y haproxy

4.2 配置

两台master节点的配置均相同，配置中声明了后端代理的两个master节点服务器，指定了haproxy运行的端口为16443等，因此16443端口为集群的入口

vi /etc/haproxy/haproxy.cfg

#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    # to have these messages end up in /var/log/haproxy.log you will
    # need to:
    # 1) configure syslog to accept network log events. This is done
    #    by adding the '-r' option to the SYSLOGD_OPTIONS in
    #    /etc/sysconfig/syslog
    # 2) configure local2 events to go to the /var/log/haproxy.log
    #   file. A line like the following can be added to
    #   /etc/sysconfig/syslog
    #
    #    local2.*                       /var/log/haproxy.log
    #
    log         127.0.0.1 local2

  chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon

    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats
#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000
#---------------------------------------------------------------------
# kubernetes apiserver frontend which proxys to the backends
#---------------------------------------------------------------------
frontend kubernetes-apiserver
    mode                 tcp
    bind                 *:16443
    option               tcplog
    default_backend      kubernetes-apiserver
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend kubernetes-apiserver
    mode        tcp
    balance     roundrobin
    server      k8s-master1   192.168.169.51:6443 check
    server      k8s-master2   192.168.169.52:6443 check
#---------------------------------------------------------------------
# collection haproxy statistics message
#---------------------------------------------------------------------
listen stats
    bind                 *:1080
    stats auth           admin:awesomePassword
    stats refresh        5s
    stats realm          HAProxy\ Statistics
    stats uri            /admin?stats

4.3 启动和检查

两台master都启动

# 设置开机启动

systemctl enable haproxy

# 开启haproxy

systemctl start haproxy

# 查看启动状态

$ systemctl status haproxy

haproxy 启动错误

ALERT] 106/093950 (115136) : Starting proxy short_message: cannot bind socket

问题1，如果bind的是vip，则需要内核添加配置/etc/sysctl.conf ，sysctl -p

net.ipv4.ip_nonlocal_bind=1

问题2，haproxy连接策略问题

执行

setsebool -P haproxy_connect_any=1

检查端口

netstat -lntup|grep haproxy

5. 所有节点安装Docker/kubeadm/kubelet

Kubernetes默认CRI（容器运行时）为Docker，因此先安装Docker。

5.1 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 --version

Docker version 18.06.1-ce, build e68fc7a

$ cat > /etc/docker/daemon.json << EOF
{
"registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"]
}
EOF

5.2 添加阿里云YUM软件源

$ 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
EOF

5.3 安装kubeadm，kubelet和kubectl

由于版本更新频繁，这里指定版本号部署：

$ yum install -y kubelet-1.16.3 kubeadm-1.16.3 kubectl-1.16.3

$ systemctl enable kubelet

6. 部署Kubernetes Master

6.1 创建kubeadm配置文件

在具有vip的master上操作，这里为master1

$ mkdir /usr/local/kubernetes/manifests -p

$ cd /usr/local/kubernetes/manifests/

$ vi kubeadm-config.yaml

apiServer:
certSANs:
    - k8s-master1
    - k8s-master2
    - k8s-vip
    - 192.168.169.50
    - 192.168.169.51
    - 192.168.169.52
    - 127.0.0.1
extraArgs:
    authorization-mode: Node,RBAC
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta1
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: "k8s-vip:16443"
controllerManager: {}
dns:
type: CoreDNS
etcd:
local:
    dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.16.3
networking:
dnsDomain: cluster.local
podSubnet: 10.244.0.0/16
serviceSubnet: 10.1.0.0/16
scheduler: {}

6.2 在master1节点执行

$ kubeadm init --config kubeadm-config.yaml (时间长。。。)

K8S集群（高可用）搭建详细过程_docker_04

**按照提示保存以下内容，一会要使用：

kubeadm join k8s-vip:16443 --token r7bcyr.5qsuutg6agg2y26r \

--discovery-token-ca-cert-hash sha256:0477cf0d297bfb040b45459354481dffffd756bb66cd6f09b527b109330b21e9

按照提示配置环境变量，使用kubectl工具：

bash

mkdir -p $HOME/.kube

cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

chown $(id -u):$(id -g) $HOME/.kube/config

kubectl get nodes

K8S集群（高可用）搭建详细过程_docker_05

kubectl get pods -n kube-system

查看集群状态

kubectl get cs

kubectl get pods -n kube-system

7.安装集群网络

从官方地址获取到flannel的yaml，在master1上执行

wget -c https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

K8S集群（高可用）搭建详细过程_Docker_06

安装flannel网络

kubectl apply -f kube-flannel.yml

K8S集群（高可用）搭建详细过程_docker_07

检查

kubectl get pods -n kube-system

K8S集群（高可用）搭建详细过程_docker_08

8、master2节点加入集群

8.1 复制密钥及相关文件

从master1复制密钥及相关文件到master2

ssh root@192.168.169.52 mkdir -p /etc/kubernetes/pki/etcd

scp /etc/kubernetes/admin.conf root@192.168.169.52:/etc/kubernetes

scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} root@192.168.169.52:/etc/kubernetes/pki

scp /etc/kubernetes/pki/etcd/ca.* root@192.168.169.52:/etc/kubernetes/pki/etcd

8.2 master2加入集群

执行在master1上init后输出的join命令,需要带上参数`--control-plane`表示把master控制节点加入集群

kubeadm join k8s-vip:16443 --token r7bcyr.5qsuutg6agg2y26r --discovery-token-ca-cert-hash sha256:0477cf0d297bfb040b45459354481dffffd756bb66cd6f09b527b109330b21e9 --control-plane

检查状态

kubectl get node

K8S集群（高可用）搭建详细过程_docker_09