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l 问题背景：检查主从复制之后做高可用报错
[root@db03 oldboy]# masterha_check_repl --conf=/etc/mha/app1.cnf
Thu May 4 21:52:24 2017 - [info] GTID (with auto-pos) is supported. Skipping all SSH and Node package checking.
Thu May 4 21:52:24 2017 - [error][/usr/share/perl5/vendor_perl/MHA/ServerManager.pm, ln492] Server 10.0.0.52(10.0.0.3306) is dead, but must be alive! Check server settings.
Thu May 4 21:52:24 2017 - [error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln424] Error happened on checkinonfigurations. at /usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm line 399
Thu May 4 21:52:24 2017 - [error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln523] Error happened on monitor servers.
Thu May 4 21:52:24 2017 - [info] Got exit code 1 (Not master dead).
MySQL Replication Health is NOT OK!
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l 解决思路：
查看部署过程有没有操作失误
根据提示Server 10.0.0.52(10.0.0.3306) is dead, but must be alive! Check server settings.判断10.0.0.52服务器连接问题
l 查看日志：
[root@db03 mha]# tail -f /var/log/mha/app1/manager
Thu May 4 17:46:00 2017 - [info] Current Alive Master: 10.0.0.51(10.0.0.51:3306)
Thu May 4 17:46:00 2017 - [info] Checking slave configurations..
Thu May 4 17:46:00 2017 - [info] Checking replication filtering settings..
Thu May 4 17:46:00 2017 - [info] binlog_do_db= , binlog_ignore_db=
Thu May 4 17:46:00 2017 - [info] Replication filtering check ok.
Thu May 4 17:46:00 2017 - [info] GTID (with auto-pos) is supported. Skipping all SSH and Node package checking.
Thu May 4 17:46:00 2017 - [error][/usr/share/perl5/vendor_perl/MHA/ServerManager.pm, ln492] Server 10.0.0.52(10.0.0.3306) is dead, but must be alive! Check server settings.
Thu May 4 17:46:00 2017 - [error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln424] Error happened on checkinonfigurations. at /usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm line 399
Thu May 4 17:46:00 2017 - [error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln523] Error happened on monitor servers.
Thu May 4 17:46:00 2017 - [info] Got exit code 1 (Not master dead).
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l 解决方法：
关闭10.0.0.52防火墙
[root@db02 MHA]# /etc/init.d/iptables stop
iptables: Setting chains to policy ACCEPT: filter [ OK ]
iptables: Flushing firewall rules: [ OK ]
iptables: Unloading modules: [ OK ]
测试结果：
Thu May 4 21:52:55 2017 - [info] Checking replication health on 10.0.0.52..
Thu May 4 21:52:55 2017 - [info] ok.
Thu May 4 21:52:55 2017 - [info] Checking replication health on 10.0.0.53..
Thu May 4 21:52:55 2017 - [info] ok.
Thu May 4 21:52:55 2017 - [warning] master_ip_failover_script is not defined.
Thu May 4 21:52:55 2017 - [warning] shutdown_script is not defined.
Thu May 4 21:52:55 2017 - [info] Got exit code 0 (Not master dead).
[root@db03 oldboy]# masterha_check_repl --conf=/etc/mha/app1.cnf
MySQL Replication Health is OK.
[root@db03 oldboy]#
########################经验小结###############################
排除故障：
原因一：防火墙iptables
原因二：selinux Disabled
原因三：软连接
ln -s /application/mysql/bin/mysqlbinlog /usr/bin/mysqlbinlog
ln -s /application/mysql/bin/mysql /usr/bin/mysql
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