[转][笔记] 6. HAProxy 负载均衡MySQL服务的配

这里的配置，是对 MySQL 的只读服务器进行负载均衡，这个配置其实很简单的，frontend 监听于 3306 端口，haproxy 工作于 tcp 模式，只有一个 backend，调度算法为最小连接数算法：

#---------------------------------------------------------------------
# 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
defaults
    mode                    tcp
    log                     global
    option                  httplog
    option                  dontlognull
    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                 600
listen stats
    mode http
    bind 0.0.0.0:1080
    stats enable
    stats hide-version
    stats uri     /haproxyadmin?stats
    stats realm   Haproxy\ Statistics
    stats auth    admin:admin
    stats admin if TRUE
frontend mysql
    bind *:3306
    mode tcp
    log global
    default_backend mysqlservers
backend mysqlservers
    balance leastconn
    server dbsrv1 192.168.10.11:3306 check port 3306 intval 2 rise 1 fall 2 maxconn 300
    server dbsrv2 192.168.10.12:3306 check port 3306 intval 2 rise 1 fall 2 maxconn 300