MySQL-Proxy实现读写分离部署文档 推荐

实验拓扑图：


实验环境说明：MySQL主从已经部署完成，并且授权mysql-proxy主机数据库权限
系统 centos 6.4 _ x86_64
192.168.0.101 mysql-proxy
192.168.0.102 mysql-master
192.168.0.103 mysql-slave
部署开始：
检查依赖包

[root@shell tools]# rpm -q lua
lua-5.1.4-4.1.el6.x86_64

2.下载通用的压缩包 mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit.tar.gz 直接解压使用

useradd -r mysql-proxy
wget http://cdn.mysql.com/Downloads/MySQL-Proxy/mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit.tar.gz tar zxf mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit.tar.gz  -C /application
ln -s /application/mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit /application/mysql-proxy

3.环境变量配置

echo "export PATH=/application/mysql-proxy/bin:$PATH" >> /etc/profile
source /etc/profile

4.启动mysql-proxy

[root@mysql-proxy ~]# mysql-proxy --daemon --log-level=debug --log-file=/var/log/mysql-proxy.log --plugins=proxy --proxy-backend-addresses="192.168.0.102:3306" --proxy-read-only-backend-addresses="192.168.0.103:3306" --proxy-lua-script="/application/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua"

5.检查启动结果

[root@mysql-proxy lib]# netstat -nltp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program name
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      971/sshd
tcp        0      0 0.0.0.0:4040                0.0.0.0:*                   LISTEN      1274/mysql-proxy
tcp        0      0 :::22

# 此时只能实现简单的读写分离
# 添加启动脚本和管理查询模块
6.为mysql-proxy服务脚本提供配置文件/etc/sysconfig/mysql-proxy

# Options for mysql-proxy
ADMIN_USER="admin"
ADMIN_PASSWORD="admin"
ADMIN_ADDRESS=""
#ADMIN_ADDRESS="0.0.0.0:4040"
ADMIN_LUA_SCRIPT="/application/mysql-proxy/share/doc/mysql-proxy/admin.lua"
PROXY_ADDRESS=""
PROXY_USER="mysql-proxy"
#PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog"

7.编辑mysql-proxy依赖的admin.lua脚本

cat >> /application/mysql-proxy/share/doc/mysql-proxy/admin.lua <<EOF
--[[ $%BEGINLICENSE%$
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
02110-1301  USA

$%ENDLICENSE%$ --]]

function set_error(errmsg)
proxy.response = {
type = proxy.MYSQLD_PACKET_ERR,
errmsg = errmsg or "error"
}
end

function 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_RESULT
end
EOF

8. 编辑mysql-proxy启动脚本

cat >> /etc/init.d/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/functions

prog="/application/mysql-proxy/bin/mysql-proxy"

# Source networking configuration.
if [ -f /etc/sysconfig/network ]; then
. /etc/sysconfig/network
fi

# Check that networking is up.
[ ${NETWORKING} = "no" ] && exit 0

# Set default mysql-proxy configuration.
ADMIN_USER="admin"
ADMIN_PASSWD="admin"
ADMIN_LUA_SCRIPT="/application/mysql-proxy/share/doc/mysql-proxy/admin.lua"
PROXY_OPTIONS="--daemon --log-level=debug --log-file=/var/log/mysql-proxy.log --plugins=proxy --plugins=admin --proxy-backend-addresses=192.168.0.102:3306 --proxy-read-only-backend-addresses=192.168.0.103:3306"
PROXY_PID=/var/run/mysql-proxy.pid
PROXY_USER="mysql-proxy"
PROXY_LUA="/application/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua"
# Source mysql-proxy configuration.
if [ -f /etc/sysconfig/mysql-proxy ]; then
. /etc/sysconfig/mysql-proxy
fi

RETVAL=0

start() {
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="$ADMIN_PASSWO
RD"
RETVAL=$?
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
;;
esac

exit $RETVAL
EOF

chmod 700 /etc/init.d/mysql-proxy
9. 重启mysql-proxy

/etc/init.d/mysql-proxy restart

10.检查启动结果

[root@mysql-proxy application]# netstat -nltpo
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program name
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      971/sshd
tcp        0      0 0.0.0.0:4040                0.0.0.0:*                   LISTEN      1396/mysql-proxy
tcp        0      0 0.0.0.0:4041                0.0.0.0:*                   LISTEN      1396/mysql-proxy
tcp        0      0 :::22                       :::*                        LISTEN      971/sshd

说明： 4040 是mysql-proxy 本身监听的端口
4040 是mysql-proxy 管理模块监听的端口
11.此时登陆管理模块，查看后端状态

mysql -uroot -P 4040 -p -h192.168.0.101 -e "select user,host from mysql.user"
mysql> select * from backends;
+-------------+--------------------+---------+------+------+-------------------+
| backend_ndx | address            | state   | type | uuid | connected_clients |
+-------------+--------------------+---------+------+------+-------------------+
|           1 | 192.168.0.102:3306 | unknown | rw   | NULL |                 0 |
|           2 | 192.168.0.103:3306 | unknown | ro   | NULL |                 0 |
+-------------+--------------------+---------+------+------+-------------------+
2 rows in set (0.00 sec)

#由于此时没有进行任何操作，所以主从状态都是unknown
12.执行查询操作，查看主从状态变化

mysql -uroot -P 4040 -p -h192.168.0.101 -e "show databases;"
mysql> select * from backends;
+-------------+--------------------+---------+------+------+-------------------+
| backend_ndx | address            | state   | type | uuid | connected_clients |
+-------------+--------------------+---------+------+------+-------------------+
|           1 | 192.168.0.102:3306 | up      | rw   | NULL |                 0 |
|           2 | 192.168.0.103:3306 | unknown | ro   | NULL |                 0 |
+-------------+--------------------+---------+------+------+-------------------+
2 rows in set (0.00 sec)

# 由于主是支持读写的，所以发现主状态变为了up是正常现象，要想观看到从的状态，需要多次查询

mysql -uroot -P 4040 -p -h192.168.0.101 -e "select user,host from mysql.user"
mysql> select * from backends;
+-------------+--------------------+-------+------+------+-------------------+
| backend_ndx | address            | state | type | uuid | connected_clients |
+-------------+--------------------+-------+------+------+-------------------+
|           1 | 192.168.0.102:3306 | up    | rw   | NULL |                 0 |
|           2 | 192.168.0.103:3306 | up    | ro   | NULL |                 0 |
+-------------+--------------------+-------+------+------+-------------------+
2 rows in set (0.00 sec)

#此时发现主从状态全部变成了up状态

附件：http://down.51cto.com/data/2364455