架构示意图
___ master_mysql(10.10.10.3) | | mysql-proxy(10.10.10.2) | |___ | slave_mysql(10.10.10.4)
(一)mysql主从同步
1、mysql-master设置
(1)
server-id = 1 //master端ID号 binlog-ignore-db = //设置不同步的sql库 binlog-do-db= //设置同步的数据
(2)设置完上面以后重启mysql
(3)添加用户访问主库,并且只有备份权限
mysql > grant replication slave on *.* to ‘rsync‘@‘10.10.%‘ identified by ‘1q2w3e4rys‘ with grant option; mysql > flush privileges;
(4)锁表,主库数据继续写入
mysql > flush tables with read lock;
(5)记录 master file与position的值,slave库配置同步时候要使用
(6)导出mysql主库数据
mysqldump -uuser -p databases > databases.sql
注:这里有个问题,当主库数据上G,较大时需要做如下操作
--max_allowed_packet=XXX //客户端/服务器之间通信的缓存区的最大大小; --net_buffer_length=XXX //TCP/IP和套接字通信缓冲区大小,创建长度达net_buffer_length的行;
注意:max_allowed_packet和net_buffer_length不能比目标数据库的配置数值大,否则可能出错。
首先确定目标库的参数值
mysql>show variables like ‘max_allowed_packet‘; mysql>show variables like ‘net_buffer_length‘;
根据参数值书写mysqldump命令,如:
mysql > mysqldump -uuser -p? 数据库名 -e --max_allowed_packet=1048576 --net_buffer_length=16384 > databases.sql
(7)master库同步到slave服务器上
# scp databases.sql [email protected]:/path
2、mysql-slave设置
(1)
server-id = 2
(2)登录mysql创建sql数据库
mysql > CREATE DATABASE `?sql_db?` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;
(3)导入master库数据到slave库中
mysql -uuser -p? sql_db < databases.sql
(4)登录mysql停止slave
mysql > stop slave;
(5)配置从库同步
mysql > change master to master_host=’10.10.10.2’,master_user=’rsync’,master_password=’1q2w3e4rys’,master_port=3306,master_log_file=’mysql-bin.000047’,master_log_pos=107;
(6)启动同步功能
mysql > start slave;
(7)解除主库锁表
unlock tables;
(8)查看slave同步状态
mysql > show slave status\G //多执行几遍,查看数据写入后的状态
注:查看上面的Slave_IO_Running: Yes 和Slave_SQL_Running: Yes 2个都为yes则证明主从同步正常,如果有任一个显示NO,则证明同步有问题.可以查看数据库日志文件,里面基本上会显示出错误之处,根据错误一步一步排查,基本上都可以解决的.
(二)mysql-proxy读写分离
1、安装mysql-proxy
(1)
# wget http://ftp.ntu.edu.tw/pub/MySQL/Downloads/MySQL-Proxy/mysql-proxy-0.8.5-linux-el6-x86-64bit.tar.gz # tar xf mysql-proxy-0.8.5-linux-el6-x86-64bit.tar.gz -C /usr/local # cd /usr/local # ln -sv mysql-proxy-0.8.5-linux-el6-x86-64bit mysql-proxy
2、设置mysql-proxy属主属组
(1)
# groupadd mysql-proxy # useradd -g mysql-proxy -s /sbin//nologin -M mysql-proxy
3、配置mysql-proxy
(1)为mysql-proxy提供SysV服务脚本,脚本如下:
#!/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
(2)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
(3)为服务脚本提供配置文件/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=10.10.10.3:3306 --proxy-read-only-backend-addresses=10.10.10.4:3306 --proxy-lua-script=/usr/local/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua"
(4)mysql-proxy配置选项注解
--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;
(5)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 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
(6)测试
#mysql -uadmin -padmin -h110.10.10.2 --port=4041 mysql > SELECT * FROM backends;
+-------------+-------------------+-------+------+------+-------------------+ | backend_ndx | address | state | type | uuid | connected_clients | +-------------+-------------------+-------+------+------+-------------------+ | 1 | 10.10.10.3:3306 | up | rw | NULL | 0 | | 2 | 10.10.10.4:3306 | up | ro | NULL | 0 | +-------------+-------------------+-------+------+------+-------------------+ 2 rows in set (0.00 sec)