MySQL 5.6 Replication

一、简单主从模式配置步骤


1、配置主从节点的服务配置文件


1.1、配置master节点：
[mysqld]
binlog-format=ROW
log-bin=master-bin
log-slave-updates=true
gtid-mode=on 
enforce-gtid-consistency=true
master-info-repository=TABLE
relay-log-info-repository=TABLE
sync-master-info=1
slave-parallel-workers=2
binlog-checksum=CRC32
master-verify-checksum=1
slave-sql-verify-checksum=1
binlog-rows-query-log_events=1
server-id=1
report-port=3306
port=3306
datadir=/mydata/data
socket=/tmp/mysql.sock
report-host=master.magedu.com


1.2、配置slave节点：
[mysqld]
binlog-format=ROW
log-slave-updates=true
gtid-mode=on 
enforce-gtid-consistency=true
master-info-repository=TABLE
relay-log-info-repository=TABLE
sync-master-info=1
slave-parallel-workers=2
binlog-checksum=CRC32
master-verify-checksum=1
slave-sql-verify-checksum=1
binlog-rows-query-log_events=1
server-id=11
report-port=3306
port=3306
log-bin=mysql-bin.log
datadir=/mydata/data
socket=/tmp/mysql.sock
report-host=slave.magedu.com


2、创建复制用户


mysql> GRANT REPLICATION SLAVE ON *.* TO repluser@172.16.100.7 IDENTIFIED BY 'replpass';


说明：172.16.100.7是从节点服务器；如果想一次性授权更多的节点，可以自行根据需要修改；


3、为备节点提供初始数据集


锁定主表，备份主节点上的数据，将其还原至从节点；如果没有启用GTID，在备份时需要在master上使用show master status命令查看二进制日志文件名称及事件位置，以便后面启动slave节点时使用。


4、启动从节点的复制线程


如果启用了GTID功能，则使用如下命令：
mysql> CHANGE MASTER TO MASTER_HOST='master.magedu.com', MASTER_USER='repluser', MASTER_PASSWORD='replpass', MASTER_AUTO_POSITION=1;


没启用GTID，需要使用如下命令：
slave> CHANGE MASTER TO MASTER_HOST='172.16.100.6',
-> MASTER_USER='repluser',
-> MASTER_PASSWORD='replpass',
-> MASTER_LOG_FILE='master-bin.000003',
-> MASTER_LOG_POS=1174;


二、半同步复制


1、分别在主从节点上安装相关的插件


master> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so';
slave> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so';


2、启用半同步复制


在master上的配置文件中，添加
rpl_semi_sync_master_enabled=ON


在至少一个slave节点的配置文件中添加
rpl_semi_sync_slave_enabled=ON


而后重新启动mysql服务即可生效。




或者，也可以mysql服务上动态启动其相关功能：


master> SET GLOBAL rpl_semi_sync_master_enabled = ON;
slave> SET GLOBAL rpl_semi_sync_slave_enabled = ON;
slave> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD;


3、确认半同步功能已经启用


master> CREATE DATABASE magedudb;
master> SHOW STATUS LIKE 'Rpl_semi_sync_master_yes_tx';


slave> SHOW DATABASES; 








三、MySQL Proxy




1、源码安装时，MySQL proxy的依赖关系：


libevent 1.x or higher (1.3b or later is preferred).
lua 5.1.x or higher.
glib2 2.6.0 or higher.
pkg-config.
libtool 1.5 or higher.
MySQL 5.0.x or higher developer files.


2、安装


# 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。


3、配置指令


mysql proxy的各配置参数请参见官方文档，http://dev.mysql.com/doc/refman/5.6/en/mysql-proxy-configuration.html












使用rpm包在rhel6上安装mysql-proxy-0.8.2，其会提供配置文件及服务脚本，但没有提供读写分享的脚本。




/etc/sysconfig/mysql-proxy文件用于定义mysql-proxy的启动参数。


ADMIN_USER – the user for the proxy's admin interface. You can leave the default admin user.
ADMIN_PASSWORD – the password for the admin user in clear text. Change the default password for better security.
ADMIN_LUA_SCRIPT – the admin script in the Lua programming language. Without this script the admin interface cannot work. You can leave the default value.
PROXY_USER – the system user under which the proxy will work. By default it is mysql-proxy, and it's safe to leave it as is.
PROXY_OPTIONS – proxy options such as logging level, plugins, and Lua scripts to be loaded.




其中PROXY_OPTIONS是最常用的一个选项，用于定义mysql-proxy工作时的重要参数，例如：
PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog --plugins=proxy --plugins=admin --proxy-backend-addresses=192.168.1.102:3306 --proxy-read-only-backend-addresses=192.168.1.105:3306 --proxy-lua-script=/usr/lib/mysql-proxy/lua/proxy/rw-splitting.lua"






















四、安装配置mysql-proxy:


4.1 下载所需要的版本，这里的系统平台为rhel6.4 32位系统，因此就以mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit.tar.gz为例。


# tar xf mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit.tar.gz -C /usr/local
# cd /usr/local
# ln -sv mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit  mysql-proxy


添加代理用户
# useradd mysql-proxy


4.2 为mysql-proxy提供SysV服务脚本，内容如下所示


#!/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


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






4.3 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"




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=172.16.100.6:3306 --proxy-read-only-backend-addresses=172.16.100.7:3306 --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。


4.4 mysql-proxy的配置选项


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；








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


6.1 管理功能测试


# mysql -uadmin -padmin -h172.16.100.107 --port=4041 


Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.0.99-agent-admin


Type 'help;' or '\h' for help. Type '\c' to clear the buffer.


mysql> SELECT * FROM backends;
+-------------+-------------------+-------+------+------+-------------------+
| backend_ndx | address           | state | type | uuid | connected_clients |
+-------------+-------------------+-------+------+------+-------------------+
|           1 | 172.16.100.6:3306 | up    | rw   | NULL |                 0 | 
|           2 | 172.16.100.7:3306 | up    | ro   | NULL |                 0 | 
+-------------+-------------------+-------+------+------+-------------------+
2 rows in set (0.00 sec)


6.2 读写分离测试


# mysql -uroot -pmagedu.com -h172.16.100.107 --port=4040