1. 简介
mysql-proxy 是官方为此的一个测试，项目， 可以完成读写分离。但是项目目前还不是很成熟，这里仅作测试。
2. mysql-proxy安装部署
# wget http://downloads.mysql.com/archives/get/file/mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit.tar.gz # tar -xf mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit.tar.gz -C /usr/local/ # cd /usr/local/ # ln -sv mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit mysql-proxy
3. 创建代理用户以及修改程序目录权限
# useradd -s /sbin/nologin -r mysql-proxy # chown -R mysql.mysql mysql-proxy-0.8.4-linux-glibc2.3-x86-64bit/
4. 提供服务脚本放在/etc/rc.d/init.d/ 下面并且给运行权限
# vim、/etc/rc.d/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="/usr/local/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="/usr/local/mysql-proxy/share/doc/mysql-proxy/admin.lua"
PROXY_OPTIONS="--daemon"
PROXY_PID=/var/run/mysql-proxy.pid
PROXY_USER="mysql-proxy"
# 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="$ADMIN_PASSWORD"
RETVAL=$?
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
;;
esac
exit $RETVAL
# chmod +x /etc/rc.d/init.d/mysql-proxy # chkconfig --add mysql-proxy
5. 为上述的服务脚本提供配置文件
创建/etc/sysconfig/mysql-proxy，内容如下所示： # Options for mysql-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 --plugins=proxy --plugins=admin --proxy-backend-addresses=192.168.98.129:3306 --proxy-read-only-backend-addresses=192.168.98.133:3306 --proxy-lua-script=/usr/local/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua" 最后一行运行选项，可以根据需要修改。 --proxy-backend-addresses= --proxy--read-only-backend-addresses= 可以指定多次，从而指定多台服务器。 其他常用选项如下 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；
6. 提供admin.lua脚本，将其保存至/usr/local/mysql-proxy/share/doc/mysql-proxy/目录中。
--[[ $%BEGINLICENSE%$
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
7. 修改一下admin.lua 脚本属主属组
# chown mysql.mysql mysql-proxy/share/doc/mysql-proxy/admin.lua
8. 在mysql主服务器上创建远程连接账户
MariaDB [(none)]> GRANT ALL ON *.* TO 'admin'@'192.168.98.%' IDENTIFIED BY 'admin'; MariaDB [(none)]> FLUSH PRIVILEGES;
9. 通过代理服务器连接服务器
注意： 实验环境中 192.168.98.129 为主服务器 192.168.98.130 为代理服务器 192.168.98.131 为从服务器 # mysql -h192.168.98.130 -uadmin -padmin root@www local]# mysql -h192.168.98.130 -uadmin -padmin Welcome to the MariaDB monitor. Commands end with ; or g. Your MariaDB connection id is 7 Server version: 10.1.9-MariaDB-log MariaDB Server Copyright (c) 2000, 2015, Oracle, MariaDB Corporation Ab and others. Type 'help;' or 'h' for help. Type 'c' to clear the current input statement. MariaDB [(none)]>
10. 使用tcpdump来验证读写请求的发往方向
向mysql-proxy请求
# for i in {1..10}; do mysql -h192.168.98.130 -uadmin -padmin -e 'select * from hellodb.students limit 1';done
在主服务器和从服务器上使用下面命令进行监控。
# tcpdump -i any -nn -XX -A -p port 3306 and src 192.168.98.130
可以发现当读请求量增大时，两边主机都可以看见读报文被截获。
向mysql-proxy执行写请求
MariaDB [hellodb]> source ~/hellodb.sql
只有在master端可以看到截获报文
尝试几次后，可以看到两个服务器状态都是up
MySQL [(none)]> SELECT * FROM backends;
+-------------+---------------------+-------+------+------+-------------------+
| backend_ndx | address | state | type | uuid | connected_clients |
+-------------+---------------------+-------+------+------+-------------------+
| 1 | 192.168.98.129:3306 | up | rw | NULL | 0 |
| 2 | 192.168.98.133:3306 | up | ro | NULL | 0 |
+-------------+---------------------+-------+------+------+-------------------+