MySQLProxy实现MySQLDB读写分离

# tar zxf mysql-proxy-0.8.2.tar.gz# cd mysql-proxy-0.8.2# ./configure# make# make check如果管理员有密码，上面的步骤则需要使用如下格式进行：# MYSQL_PASSWORD=root_pwd make check# make install默认情况下， mysql-proxy安装在/usr/local/sbin/mysql-proxy，而Lua示例脚本安装在/usr/local/share目录中。

[root@httpweb ~]# wget http://mirror.sohu.com/mysql/MySQL-Proxy/mysql-proxy-0.8.4-linux-el6-x86-bit.tar.gz[root@httpweb ~]# tar xf mysql-proxy-0.8.4-linux-el6-x86-bit.tar.gz[root@httpweb ~]# mv mysql-proxy-0.8.4-linux-el6-x86-bit /usr/local/mysql-proxy

[root@httpweb mysql-proxy]# useradd mysql-proxy

#!/bin/bash## mysql-proxy This script starts and stops the mysql-proxy daemon## chkconfig: - 78 30# processname: mysql-proxy# description: mysql-proxy is a proxy daemon for mysql# Source function library.. /etc/rc.d/init.d/functionsprog="/usr/local/mysql-proxy/bin/mysql-proxy"# Source networking configuration.if [ -f /etc/sysconfig/network ]; then	. /etc/sysconfig/networkfi# Check that networking is up.[ ${NETWORKING} = "no" ] && exit 0# Set default mysql-proxy configuration.ADMIN_USER="admin"ADMIN_PASSWD="admin"ADMIN_LUA_SCRIPT="/usr/local/mysql-proxy/share/doc/mysql-proxy/admin.lua"PROXY_OPTIONS="--daemon"PROXY_PID=/var/run/mysql-proxy.pidPROXY_USER="mysql-proxy"# Source mysql-proxy configuration.if [ -f /etc/sysconfig/mysql-proxy ]; then	. /etc/sysconfig/mysql-proxyfiRETVAL=0start() {	echo -n $"Starting $prog: "	daemon $prog $PROXY_OPTIONS --pid-file=$PROXY_PID --proxy-address="$PROXY_ADDRESS" --user=$PROXY_USER --admin-username="$ADMIN_USER" --admin-lua-script="$ADMIN_LUA_SCRIPT" --admin-password="$ADMIN_PASSWORD"	RETVAL=$?	echo	if [ $RETVAL -eq 0 ]; then	touch /var/lock/subsys/mysql-proxy	fi}stop() {	echo -n $"Stopping $prog: "	killproc -p $PROXY_PID -d 3 $prog	RETVAL=$?	echo	if [ $RETVAL -eq 0 ]; then	rm -f /var/lock/subsys/mysql-proxy	rm -f $PROXY_PID	fi}# See how we were called.case "$1" in	start)	start	;;	stop)	stop	;;	restart)	stop	start	;;	condrestart|try-restart)	if status -p $PROXY_PIDFILE $prog >&/dev/null; then	stop	start	fi	;;	status)	status -p $PROXY_PID $prog	;;	*)	echo "Usage: $0 {start|stop|restart|reload|status|condrestart|try-restart}"	RETVAL=1	;;esacexit $RETVAL

[root@httpweb mysql-proxy]# vi /etc/init.d/mysql-proxy[root@httpweb mysql-proxy]# chmod +x /etc/init.d/mysql-proxy[root@httpweb mysql-proxy]# chkconfig --add mysql-proxy

#Options for mysql-proxyADMIN_USER="firefox"ADMIN_PASSWORD="firefox"ADMIN_ADDRESS=""ADMIN_LUA_SCRIPT="/usr/local/mysql-proxy/share/doc/mysql-proxy/admin.lua"PROXY_ADDRESS=""PROXY_USER="mysql-proxy"PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog --plugins=proxy --plugins=admin --proxy-backend-addresses=192.168.1.200:3306 --proxy-read-only-backend-addresses=192.168.1.202:3306 --proxy-lua-script=/usr/local/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua"其中的proxy-backend-addresses选项和proxy-read-only-backend-addresses选项均可重复使用多次，以实现指定多个读写服务器或只读服务器。

mysql-proxy的配置选项大致可分为帮助选项、管理选项、代理选项及应用程序选项几类，下面一起去介绍它们。	--help	--help-admin	--help-proxy	--help-all ———— 以上四个选项均用于获取帮助信息；	--proxy-address=host:port ———— 代理服务监听的地址和端口；	--admin-address=host:port ———— 管理模块监听的地址和端口；	--proxy-backend-addresses=host:port ———— 后端mysql服务器的地址和端口；	--proxy-read-only-backend-addresses=host:port ———— 后端只读mysql服务器的地址和端口；	--proxy-lua-script=file_name ———— 完成mysql代理功能的Lua脚本；	--daemon ———— 以守护进程模式启动mysql-proxy；	--keepalive ———— 在mysql-proxy崩溃时尝试重启之；	--log-file=/path/to/log_file_name ———— 日志文件名称；	--log-level=level ———— 日志级别；	--log-use-syslog ———— 基于syslog记录日志；	--plugins=plugin,.. ———— 在mysql-proxy启动时加载的插件；	--user=user_name ———— 运行mysql-proxy进程的用户；	--defaults-file=/path/to/conf_file_name ———— 默认使用的配置文件路径；其配置段使用[mysql-proxy]标识；	--proxy-skip-profiling ———— 禁用profile；	--pid-file=/path/to/pid_file_name ———— 进程文件名； 

--[[ $%BEGINLICENSE%$ Copyright (c) 2007, 2012, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301USA $%ENDLICENSE%$ --]]function set_error(errmsg)	proxy.response = {	type = proxy.MYSQLD_PACKET_ERR,	errmsg = errmsg or "error"	}endfunction read_query(packet)	if packet:byte() ~= proxy.COM_QUERY then	set_error("[admin] we only handle text-based queries (COM_QUERY)")	return proxy.PROXY_SEND_RESULT	end	local query = packet:sub(2)	local rows = { }	local fields = { }	if query:lower() == "select * from backends" then	fields = {	{ name = "backend_ndx",	type = proxy.MYSQL_TYPE_LONG },	{ name = "address",	type = proxy.MYSQL_TYPE_STRING },	{ name = "state",	type = proxy.MYSQL_TYPE_STRING },	{ name = "type",	type = proxy.MYSQL_TYPE_STRING },	{ name = "uuid",	type = proxy.MYSQL_TYPE_STRING },	{ name = "connected_clients",	type = proxy.MYSQL_TYPE_LONG },	}	for i = 1, #proxy.global.backends do	local states = {	"unknown",	"up",	"down"	}	local types = {	"unknown",	"rw",	"ro"	}	local b = proxy.global.backends[i]	rows[#rows + 1] = {	i,	b.dst.name,	-- configured backend address	states[b.state + 1], -- the C-id is pushed down starting at 0	types[b.type + 1], -- the C-id is pushed down starting at 0	b.uuid,	-- the MySQL Server's UUID if it is managed	b.connected_clients-- currently connected clients	}	end	elseif query:lower() == "select * from help" then	fields = {	{ name = "command",	type = proxy.MYSQL_TYPE_STRING },	{ name = "description",	type = proxy.MYSQL_TYPE_STRING },	}	rows[#rows + 1] = { "SELECT * FROM help", "shows this help" }	rows[#rows + 1] = { "SELECT * FROM backends", "lists the backends and their state" }	else	set_error("use 'SELECT * FROM help' to see the supported commands")	return proxy.PROXY_SEND_RESULT	end	proxy.response = {	type = proxy.MYSQLD_PACKET_OK,	resultset = {	fields = fields,	rows = rows	}	}	return proxy.PROXY_SEND_RESULTend

service mysql-proxy start

MariaDB [(none)]>grant all on *.* to 'firefox'@'192.168.1.201' identified by 'firefox';MariaDB [(none)]> flush privileges;[root@httpweb mysql-proxy]# mysql -ufirefox -pfirefox -h192.168.1.201 --port=3306我们可以看到我们在mysql-proxy的可以登录数据库了

[root@httpweb ~]# mysql -ufirefox -pfirefox -h192.168.1.201 --port=4041Welcome to the MySQL monitor.Commands end with ; or /g.Your MySQL connection id is 1Server version: 5.0.99-agent-adminCopyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.Oracle is a registered trademark of Oracle Corporation and/or itsaffiliates. Other names may be trademarks of their respectiveowners.mysql> select * from backends;+-------------+--------------------+---------+------+------+-------------------+| backend_ndx | address| state | type | uuid | connected_clients |+-------------+--------------------+---------+------+------+-------------------+| 1 | 192.168.1.200:3306 | up| rw | NULL | 0 || 2 | 192.168.1.202:3306 | up| ro | NULL | 0 |+-------------+--------------------+---------+------+------+-------------------+