一、安装MHA基本环境
1. 安装MHA node
(1) 基本环境说明，本文参考互联网文章学习，搭建MHA与测试如下。
参考文档：
角色 IP地址 主机名
=============================================
Master 192.168.1.121 node1
Slave 192.168.1.122 node2
Slave 192.168.1.123 node3
Monitor host 192.168.1.125 node5
(2) 在node1,node2,node3,node5操作：
# vi /etc/hosts
192.168.1.121 node1
192.168.1.122 node2
192.168.1.123 node3
192.168.1.125 node5
安装MHA node节点软件包：
# rpm -ivh Fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
# yum install perl-DBD-MySQL perl-CPAN -y
# tar xf mha4mysql-node-0.56.tar.gz
# cd mha4mysql-node-0.56
# perl Makefile.PL
# make && make install
2. 安装MHA Manager
在node5管理节点上操作：注：MHA Manager主机也是需要安装MHA Node,MHA Manger
# yum install perl-DBD-MySQL perl-CPAN perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager perl-Time-HiRes -y
# tar xf mha4mysql-manager-0.56.tar.gz
# cd mha4mysql-manager-0.56
# perl Makefile.PL
# make && make install
#说明：安装的脚本程序都在/usr/local/bin/目录下。
3. 节点间配置SSH登录无密码验证（MHA主机之间使用key登录）
在node5（Monitor）：
# ssh-keygen -t rsa
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node1
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node2
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node3
在node1（Master）：
# ssh-keygen -t rsa
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node2
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node3
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node5
在node2 (slave)：
# ssh-keygen -t rsa
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node1
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node3
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node5
在node3 (slave)：
# ssh-keygen -t rsa
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node1
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node2
# ssh-copy-id -i /root/.ssh/id_rsa.pub root@node5
二、搭建主从复制环境
1. 主从复制环境配置过程
(1) mysql安装过程略,但是三节点要创建如下链接
node1(主)，node2(主备从）,node3(从)
注意：创建如下链接：
ln -s /usr/local/mysql/bin/* /usr/local/bin/
node1 my.cnf
server-id = 1
binlog-format = ROW
log-bin = master-bin
log-bin-index = master-bin.index
log-slave-updates = true
relay_log_purge = 0
node2 my.cnf
server-id = 2
binlog-format = ROW
log-bin = master-bin
log-bin-index = master-bin.index
log-slave-updates = true
relay_log_purge = 0
node3 my.cnf
binlog-format = ROW
log-bin = mysql-bin
relay-log = slave-relay-bin
relay-log-index = slave-relay-bin.index
log-slave-updates = true
server-id = 11
skip-name-resolve
relay_log_purge = 0
(2) 在node1 (Master)上备份一份完整的数据：
# mysqldump -uroot -p123456 --master-data=2 --single-transaction -R --triggers -A > all.sql
其中--master-data=2代表备份时刻记录master的Binlog位置和Position。
(3) 在node1 (Master)上创建复制用户:
mysql> grant replication slave on *.* to 'repl'@'192.168.1.%' identified by '123456';
mysql> flush privileges;