HAProxy 实现 mysql 负载均衡

通过yum 安装和配置HAProxy

# yum install -y haproxy     #安装haproxy
# rpm -qa | grep haproxy     #查看安装的haproxy信息
# rpm -ql haproxy-1.5.18-7.el7.x86_64     #查看配置文件位置
# vim /etc/haproxy/haproxy.cfg
#---------------------------------------------------------------------
# Example configuration for a possible web application.  See the
# full configuration options online.
#
#   http://haproxy.1wt.eu/download/1.4/doc/configuration.txt
#
#---------------------------------------------------------------------
#---------------------------------------------------------------------
# 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
#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
#frontend  main *:5000
#    acl url_static       path_beg       -i /static /images /javascript /stylesheets
#    acl url_static       path_end       -i .jpg .gif .png .css .js
 #   use_backend static          if url_static
 #   default_backend             app
#---------------------------------------------------------------------
# static backend for serving up images, stylesheets and such
#---------------------------------------------------------------------
#backend static
#    balance     roundrobin
#    server      static 127.0.0.1:4331 check
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
listen  mysql
        bind 0.0.0.0:5000 #绑定端口
        mode tcp
        balance roundrobin   #轮询
        server  mysql3316 xxx.xxx.xxx.xxx:3316  check inter 2000 fall 3 weight 30
        server  mysql3326 xxx.xxx.xxx.xxx:3326  check inter 2000 fall 3 weight 30
# systemctl start haproxy    #启动haproxy
# systemctl status haproxy   #查看haproxy服务状态

新建数据库连接

连接数据库，查询数据

断开数据库重连，查询数据

验证负载均衡配置成功