Haproxy、Keepalived双主高可用负载均衡

集合Haproxy,Keepalived双主双机高可用模型,不论是Haproxy还是Keepalived甚至是上游服务器均提高生产力并增强可用性,也就是如下架构中Haproxy,Keepalived,Httpd服务器任意宕机一台服务还是可以正常运行的

规划:

172.16.43.1 , 172.16.43.2 两台keepalived节点 (为haproxy做高可用)
172.16.43.1(172.16.43.2)  两台haproxy (为上游服务器做反带)
172.16.43.3 , 172.16.43.4 两台web后端服务器

i) 两台keepalived节点

# 安装keepalived, 两台均要做 (172.16.43.1,2)
yum -y install keepalived
#
# keepalived配置 (172.16.43.1)
# vim /etc/keepalived/keepalived.conf
#
global_defs {
    notification_email {
        root@localhost  # 本地邮件地址
    }
    notification_email_from keepadmin@localhost
    smtp_connect_timeout 3
    smtp_server 127.0.0.1
    router_id LVS_DEVEL_KING
}
#
vrrp_script chk_haproxy {
    script "/etc/keepalived/chk_haproxy.sh"  # 检查脚本
    interval 2
    weight 2
}
#
vrrp_instance VI_1 {
    interface eth0
    state MASTER  # 172.16.43.1 这是主,那么 172.16.43.2 就是备
    priority 100  # 主 比 备 优先级高
    virtual_router_id 173   # vrid是行为vmac的根本
    garp_master_delay 1
#
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_interface {
        eth0
    }
    virtual_ipaddress {
        172.16.43.88/16 dev eth0
    }
    track_script {
        chk_haproxy  # 脚本跟踪监测
    }
}
#
vrrp_instance VI_2 {
    interface eth0
    state BACKUP  # master for slave routers
    priority 99  # 99 for master
    virtual_router_id 174
    garp_master_delay 1
#
    authentication {
        auth_type PASS
        auth_pass 11111
    }
    track_interface {
        eth0
    }
    virtual_ipaddress {
        172.16.43.188/16 dev eth0
    }
}

# 172.16.43.2 keepalived配置
# vim /etc/keepalived/keepalived.conf
#
global_defs {
    notification_email {
        root@localhost
    }
    notification_email_from keepadmin@localhost
    smtp_connect_timeout 3
    smtp_server 127.0.0.1
    router_id LVS_DEVEL_KING
}
#
vrrp_script chk_haproxy {
    script "/etc/keepalived/chk_haproxy.sh"
    interval 2
    weight 2
}
#
vrrp_instance VI_1 {
    interface eth0
    state BACKUP  # BACKUP for slave routers
    priority 99  # 99 for BACKUP
    virtual_router_id 173
    garp_master_delay 1
#
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_interface {
        eth0
    }
    virtual_ipaddress {
        172.16.43.88/16 dev eth0
    }
    track_script {
        chk_haproxy
    }
}
#
vrrp_instance VI_2 {
    interface eth0
    state MASTER  # master for slave routers
    priority 10000  # 99 for master
    virtual_router_id 174
    garp_master_delay 1
#
    authentication {
        auth_type PASS
        auth_pass 11111
    }
    track_interface {
        eth0
    }
    virtual_ipaddress {
        172.16.43.188/16 dev eth0
    }
}

# 刚才两个节点 均要有 的监测脚本文件 , 防止 haproxy 停止而 keepalived 不切换的情况
# vim /etc/keepalived/chk_haproxy.sh
#
#
#!/bin/bash
#
if ! `pidof haproxy &> /dev/null`; then
    /etc/rc.d/init.d/haproxy  start
fi
sleep 2
if ! `pidof haproxy &> /dev/null`; then
    /etc/rc.d/init.d/keepalived stop
fi

###   启动服务   ####    service keepalived start

keepalived双主模型启动

ii) 两台haproxy

# 安装haproxy,两台均要 (172.16.43.1 , 2)
yum -y install haproxy
#
# 为haproxy分别提供配置文件 , 两台均一样 , 不需要更改
global
    log         127.0.0.1 local2
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon
#
defaults
    mode                    http  # http tcp health 模型, 这里监控 web 站点所以使用 http
    log                     global
    option                  httplog
    option                  dontlognull
    option                  redispatch  # 调度到健康的服务器
    option http-server-close # 不接受长连接
    option forwardfor       except 127.0.0.0/8  # 在响应头中加入forwardfor标记
    retries                 3
    timeout http-request    10s  # 超时时间设置
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 30000
#
listen stats
    mode http
    bind 0.0.0.0:8080   # status 页面在8080提供服务
    stats enable   #  status 允许操作
    stats hide-version # status 隐藏haproxy版本信息
    stats uri     /haproxyadmin?stats  # status 访问路径
    stats realm   Haproxy\ Statistics  # status 登陆验证信息
    stats auth    admin:admin  # status 页面登陆用户名或密码
    stats admin if TRUE
#
frontend http-in
    bind *:80
    mode http
    log global
    option httpclose
    option logasap
    option dontlognull
    capture request  header Host len 20
    capture request  header Referer len 60
    acl url_static       path_beg       -i /static /images /javascript /stylesheets
    acl url_static       path_end       -i .html .jpg .jpeg .gif .png .css .js
#
    use_backend static_servers          if url_static
    default_backend dynamic_servers
#
backend static_servers
    balance roundrobin
    server imgsrv1 172.16.43.3:80 check maxconn 6000
#
backend dynamic_servers
    balance source
    server websrv1 172.16.43.3:80 check maxconn 1000
    server websrv2 172.16.43.4:80 check maxconn 1000

###   启动服务   ####    service haproxy start

输出状态页面

iii) 两台web后端服务器

# 安装 httpd , php
yum -y
install httpd php

###   启动服务   ####    service httpd start

iv) 测试

动静分离

高可用性

关闭了上游一台web服务器,可以见到服务请求没有任何问题, 172.16.43.88 , 188 没有问题