Kubernetes安装之一：HA-高可用配置

       Kubernetes 一直没有自己的高可用方案，从yum安装1.5.2开始到使用阿里云自带的Kubernetes集群，一直没有自己手动安装配置过这个高可用方案，在过年前终于自己安装配置了一次，也是参考各路大神的文章，现在年过完了，准备把安装过程记录下来，我的安装会比较特殊，仅供各位参考：

操作系统最小化安装centos 7.3 

1.修改主机名

hostnamectl set-hostname  host40
hostnamectl set-hostname  host41
hostnamectl set-hostname  host42

2.关闭防火墙和selinux

systemctl stop firewalld
systemctl disable firewalld
sed -i 's/enforcing/disabled/g' /etc/selinux/config
setenforce 0

3.安装基础软件 

yum -y install keepalived haproxy  psmisc

4.配置haproxy

三台机器启动haproxy ，监听8443端口代理最后的api-service，10080端口作为haproxy状态监控

cat>/etc/haproxy/haproxy.cfg<<EOF
global
    log /dev/log    local0
    log /dev/log    local1 notice
    chroot /var/lib/haproxy
    stats socket /tmp/admin.sock mode 660 level admin
    stats timeout 30s
    user haproxy
    group haproxy
    daemon
    nbproc 1
    
defaults
    log     global
    timeout connect 5000
    timeout client  10m
    timeout server  10m

listen  admin_stats
    bind 0.0.0.0:10080
    mode http
    log 127.0.0.1 local0 err
    stats refresh 30s 
    stats uri /status
    stats realm welcome login\ Haproxy
    stats auth admin:123456
    stats hide-version
    stats admin if TRUE

 listen kube-master
     bind 0.0.0.0:8443
     mode tcp
     option tcplog
     balance source
     server 192.168.1.40 192.168.1.40:6443 check inter 2000 fall 2 rise 2 weight 1
     server 192.168.1.41 192.168.1.41:6443 check inter 2000 fall 2 rise 2 weight 1
     server 192.168.1.42 192.168.1.42:6443 check inter 2000 fall 2 rise 2 weight 1
EOF

启动haproxy，如果有错误，请根据错误提示解决(我在处理的时候因为sock文件地址权限的问题遇到过错误，所以我这里把他切换到tmp目录，避免权限问题)

systemctl daemon-reload
systemctl enable haproxy
systemctl restart haproxy
systemctl status haproxy

5.配置keepalived

5.1配置服务器a keepalived

cat > /etc/haproxy/haproxy.cfg <<EOF
global_defs {
    router_id k8s-master
}

vrrp_script check-haproxy {
    script "killall -0 haproxy"
    interval 5
    weight -30
}

vrrp_instance VI-kube-master {
    state MASTER
    priority 150
    nopreempt 
    dont_track_primary
    interface eth0
    virtual_router_id 68
    advert_int 3
    track_script {
        check-haproxy
    }
    virtual_ipaddress {
        192.168.1.43/24 dev eth0 label eth0:1
    }
}
EOF

5.2 配置服务器b keepalived 

cat > /etc/keepalived/keepalived.conf <<EOF
global_defs {
    router_id k8s-slave1
}

vrrp_script check-haproxy {
    script "killall -0 haproxy"
    interval 5
    weight -30
}

vrrp_instance VI-kube-master {
    state BACKUP
    priority 100
    nopreempt 
    dont_track_primary
    interface eth0
    virtual_router_id 68
    advert_int 3
    track_script {
        check-haproxy
    }
    virtual_ipaddress {
        192.168.1.43/24 dev eth0 label eth0:1
    }
}
EOF

5.3 配置服务器c keepalived

cat > /etc/keepalived/keepalived.conf <<EOF
global_defs {
    router_id k8s-slave2
}

vrrp_script check-haproxy {
    script "killall -0 haproxy"
    interval 5
    weight -30
}

vrrp_instance VI-kube-master {
    state BACKUP
    priority 50
    nopreempt 
    dont_track_primary
    interface eth0
    virtual_router_id 68
    advert_int 3
    track_script {
        check-haproxy
    }
    virtual_ipaddress {
        192.168.1.43/24 dev eth0 label eth0:1
    }
}
EOF

6.启动keepalived

systemctl daemon-reload
systemctl enable keepalived
systemctl restart keepalived
systemctl status keepalived

以上配置实现服务器 vip 默认在a服务器，如果a宕机则vip到b服务器，如果ab 都宕机 则vip到c服务器

如果把abc服务器都设置BACKUP 则第一次启动都不会获得VIP

你们可以把你们的发我参考下 实现第一次启动会获得VIP  切换以后也不会漂移回去的配置

首先完成ha的配置因为后面的配置需要调用vip的地址