node3
192.168.3.26 mmm
为了省事，在一个节点配置，然后拷贝到其它节点即可；配置完成后，可以相互ping一下主机名，看能否成功解析。
5.搭建MySQL主从复制
按照规划，在node1、node2、node3上安装MySQL数据库，并搭建成一主二从的MySQL Replication结构；具体操作不做说明了，可参考http://blog.csdn.net/dbaxiaosa/article/details/22421969 对于MHA来说，搭建MySQL Replication需要注意以下几点：
? read_only??是否限制Slave实例为只读状态，缺省为0，即不限制，MHA要求设置为1。
? relay_log_purge??这个参数用于限制中继日志应用完之后是否删除，缺省为1，即应用完之后立即删除；在MHA中，Manager就是通过这些日志来同步各个Slave之间的数据差异的，所以必须设置为0，即不删除中继日志。
? log_bin??是否开启二进制日志，若某个Slave可能被选择成为新的Master，则必须开启；若某个Slave被限制永远不会成为新的Master，可以不用开启。
成功搭建后，通过MHA命令检查一下，确保无误。
[root@mmm scripts]# /usr/bin/masterha_check_repl --conf=/etc/appl.cnf
Mon Jul 21 10:40:12 2014 - [info] Reading default configuratoins from /etc/masterha_default.cnf..
Mon Jul 21 10:40:12 2014 - [info] Reading application default configurations from /etc/appl.cnf..
Mon Jul 21 10:40:12 2014 - [info] Reading server configurations from /etc/appl.cnf..
Mon Jul 21 10:40:12 2014 - [info] MHA::MasterMonitor version 0.55.
Mon Jul 21 10:40:12 2014 - [info] Dead Servers:
Mon Jul 21 10:40:12 2014 - [info] Alive Servers:
Mon Jul 21 10:40:12 2014 - [info] 192.168.3.27(192.168.3.27:3306)
Mon Jul 21 10:40:12 2014 - [info] 192.168.3.28(192.168.3.28:3306)
Mon Jul 21 10:40:12 2014 - [info] 192.168.3.25(192.168.3.25:3306)
Mon Jul 21 10:40:12 2014 - [info] Alive Slaves:
Mon Jul 21 10:40:12 2014 - [info] 192.168.3.28(192.168.3.28:3306) Version=5.5.17-log (oldest major version between slaves) log-bin:enabled
Mon Jul 21 10:40:12 2014 - [info] Replicating from 192.168.3.27(192.168.3.27:3306)
Mon Jul 21 10:40:12 2014 - [info] Primary candidate for the new Master (candidate_master is set)
Mon Jul 21 10:40:12 2014 - [info] 192.168.3.25(192.168.3.25:3306) Version=5.5.17 (oldest major version between slaves) log-bin:disabled
Mon Jul 21 10:40:12 2014 - [info] Replicating from 192.168.3.27(192.168.3.27:3306)
Mon Jul 21 10:40:12 2014 - [info] Not candidate for the new Master (no_master is set)
Mon Jul 21 10:40:12 2014 - [info] Current Alive Master: 192.168.3.27(192.168.3.27:3306)
Mon Jul 21 10:40:12 2014 - [info] Checking slave configurations..
Mon Jul 21 10:40:12 2014 - [warning] relay_log_purge=0 is not set on slave 192.168.3.28(192.168.3.28:3306).
Mon Jul 21 10:40:12 2014 - [warning] log-bin is not set on slave 192.168.3.25(192.168.3.25:3306). This host can not be a master.
Mon Jul 21 10:40:12 2014 - [info] Checking replication filtering settings..
Mon Jul 21 10:40:12 2014 - [info] binlog_do_db= , binlog_ignore_db=
Mon Jul 21 10:40:12 2014 - [info] Replication filtering check ok.
Mon Jul 21 10:40:12 2014 - [info] Starting SSH connection tests..
Mon Jul 21 10:40:13 2014 - [info] All SSH connection tests passed successfully.
Mon Jul 21 10:40:13 2014 - [info] Checking MHA Node version..
Mon Jul 21 10:40:14 2014 - [info] Version check ok.
Mon Jul 21 10:40:14 2014 - [info] Checking SSH publickey authentication settings on the current master..
Mon Jul 21 10:40:14 2014 - [info] HealthCheck: SSH to 192.168.3.27 is reachable.
Mon Jul 21 10:40:14 2014 - [info] Master MHA Node version is 0.54.
Mon Jul 21 10:40:14 2014 - [info] Checking recovery script configurations on the current master..
Mon Jul 21 10:40:14 2014 - [info] Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/data/lib/mysql --output_file=/mha/appl/save_binary_logs_test --manager_version=0.55 --start_file=mysql-bin.000004
Mon Jul 21 10:40:14 2014 - [info] Connecting to ro