MariaDB Proxy读写分离的实现

MariaDB Proxy读写分离的实现

1.创建用于存储数据目录lvm设备

安装mysql-proxy-0.8.3

为mysql-proxy提供SysV服务脚本，内容如下所示
# vim /etc/rc.d/init.d/mysql-proxy

#!/bin/bash

#

# mysql-proxy Thisscript starts and stops the mysql-proxy daemon

#

# chkconfig: - 7830

# processname:mysql-proxy

# description:mysql-proxy is a proxy daemon for mysql

# Source functionlibrary.

./etc/rc.d/init.d/functions

prog="/usr/local/mysql-proxy/bin/mysql-proxy"

# Sourcenetworking configuration.

if [ -f/etc/sysconfig/network ]; then

. /etc/sysconfig/network

fi

# Check thatnetworking is up.

[ ${NETWORKING} = "no"] && exit 0

# Set defaultmysql-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.pid

PROXY_USER="mysql-proxy"

# Sourcemysql-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_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 werecalled.

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

将上述内容保存为/etc/rc.d/init.d/mysql-proxy，给予执行权限，而后加入到服务列表。

# chmod +x /etc/rc.d/init.d/mysql-proxy

# chkconfig --add mysql-proxy

为服务脚本提供配置文件/etc/sysconfig/mysql-proxy，内容如下所示：

# Options formysql-proxy

ADMIN_USER="admin"

ADMIN_PASSWORD="admin"

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"

其中最后一行，需要按实际场景进行修改，例如：

PROXY_OPTIONS="--daemon--log-level=info --log-use-syslog --plugins=proxy --plugins=admin--proxy-backend-addresses=172.16.251.68:3306--proxy-read-only-backend-addresses=172.16.251.69:3306--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。

复制如下内容建立admin.lua文件，将其保存至/usr/local/mysql-proxy/share/doc/mysql-proxy/目录中。

--[[$%BEGINLICENSE%$

Copyright (c) 2007, 2012, Oracle and/or itsaffiliates. All rights reserved.

This program is free software; you canredistribute it and/or

modify it under the terms of the GNU GeneralPublic License as

published by the Free Software Foundation;version 2 of the

License.

This program is distributed in the hope thatit will be useful,

but WITHOUT ANY WARRANTY; without even theimplied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULARPURPOSE. See the

GNU General Public License for more details.

You should have received a copy of the GNUGeneral Public License

along with this program; if not, write to theFree Software

Foundation, Inc., 51 Franklin St, Fifth Floor,Boston, MA

02110-1301USA

$%ENDLICENSE%$ --]]

functionset_error(errmsg)

proxy.response = {

type = proxy.MYSQLD_PACKET_ERR,

errmsg = errmsg or "error"

}

end

functionread_query(packet)

if packet:byte() ~= proxy.COM_QUERY then

set_error("[admin] we only handletext-based queries (COM_QUERY)")

return proxy.PROXY_SEND_RESULT

end

local query = packet:sub(2)

local rows = { }

local fields = { }

if query:lower() == "select * frombackends" 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-idis 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 itis managed

b.connected_clients-- currently connected clients

}

end

elseif query:lower() == "select * fromhelp" then

fields = {

{ name = "command",

type =proxy.MYSQL_TYPE_STRING },

{ name = "description",

type = proxy.MYSQL_TYPE_STRING },

}

rows[#rows + 1] = { "SELECT * FROMhelp", "shows this help" }

rows[#rows + 1] = { "SELECT * FROMbackends", "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

仅启动mysql-proxy就可以了，不要启动MariaDB,否则你只会看到mysql的3306端口

# service mysql-proxy start

# ss –tnl|egrep ":3306|:4401"

LISTEN  0  128   *:4041  *:*    users:(("mysql-proxy",3592,11))

LISTEN  0  128   *:3306  *:*    users:(("mysql-proxy",3592,10))

MySQL Master端

在MySQL Master端(172.16.251.69)授权

#mysql

mysql> GRANT ALL ON*.* TO 'admin'@'172.16.%.%' IDENTIFIED BY 'admin';

mysql> FLUSHPRIVILEGES;

MySQL Slave端

在MySQL Slave端的数据库上查看是否有授权的用户

测试

下面的操作均在Maridb Proxy(172.16.251.70)上执行

管理功能测试

此时，若我们还试图以传统的方式连接Mysql的话，很显然是会失败的，如下：

# mysql

ERROR 2002(HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'(2 "No such file or directory")

正确的方式：

[root@station150 ~]#mysql-uadmin -padmin -h172.16.251.70 --port=4041

Welcome to theMariaDB monitor.Commands end with ; or\g.

Your MySQLconnection id is 1

Server version:5.0.99-agent-admin

MySQL [(none)]> SELECT* FROM HELP;

MySQL [(none)]>SELECT * FROM backends;

+-------------+--------------------+---------+------+------+-------------------+

| backend_ndx |address| state| type | uuid | connected_clients |

+-------------+--------------------+---------+------+------+-------------------+

|1 | 172.16.251.69:3306 | unknown |rw| NULL |0 |

|2 | 172.16.251.68:3306 | unknown |ro| NULL |0 |

+-------------+--------------------+---------+------+------+-------------------+

2 rows in set (0.01sec)

读写分离测试

通过MariadbProxy(172.16.251.70)访问Master MySQL(172.16.251.69)的数据库

# mysql -uadmin-padmin -h172.16.251.70 [--port=3306]

(1)测试写操作

# mysql -uadmin -padmin-h172.16.251.70

然后分别去Master端和Slave端，验证是否能看通过Mariadb Proxy新建的mydb1数据库

通过Mariadb Proxy删除hellodb数据库及其中的数据，并验证

MariaDB Proxy 70
执行批量导入数据的操作：

验证读写分离的最好办法是：分别在Master(可读写)，Slave(只读)上使用tcpdump抓包工具，看可以捕捉到哪种操作的数据报文

测试读操作

在Master上捕获到的和读写操作相关的报文

由于在Master上可以进行读写操作，所以当读(查询)操作较少的时候，基本上Master自身就处理了，

所以想要验证效果就必须批量导入数据或执行查询操作。

在MariadbProxy(70)执行批量读操作

# for i in `seq10`;do mysql -uadmin -padmin -h172.16.251.70 -e "select * fromhellodb.classes where ClassID=$i";done

下面是批量执行读操作时，在Slave上捕获到的和读写操作相关的报文

朋友，还记得之前在MariaDBProxy上执行SELECT * FROM backends;时state栏的状态信息吗？

刚开执行读写操作的时候，只有Master(172.16.251.69)的state是up状态，而在我批量执行读操作之后，

现在Slave(172.16.251.68)的state也变成了up状态，表示Slave端已接受到了读请求