MySQL 有关MHA搭建与切换的几个错误log

1：masterha_check_repl 副本集方面报错  replicates is not defined in the configuration file!

具体信息如下：

# /usr/local/bin/masterha_check_repl --conf=/etc/mha/app1.cnf

Thu Nov  ::  - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Thu Nov  ::  - [info] Reading application default configuration from /etc/mha/app1.cnf..
Thu Nov  ::  - [info] Reading server configuration from /etc/mha/app1.cnf..
Thu Nov  ::  - [info] MHA::MasterMonitor version 0.56.
Thu Nov  :: - [error][/usr/local/share/perl5/MHA/ServerManager.pm, ln671] Master 179.179.19.179: from which slave 179.179.19.180(179.179.19.180:) replicates is not defined in the configuration file!
Thu Nov  ::  - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln424] Error happened on checking configurations.  at /usr/local/share/perl5/MHA/MasterMonitor.pm line .
Thu Nov  ::  - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln523] Error happened on monitoring servers.
Thu Nov  ::  - [info] Got exit code  (Not master dead).
 
MySQL Replication Health is NOT OK!

分析：MHA 漂移过后，我们知道配置信息中 主节点的信息就不在了，我们需要及时维护，否则/usr/local/bin/masterha_check_repl --conf=/etc/mha/XXX.cnf 检查副本集状态报错。

2. masterha_master_switch 在线切换方面 报错 We should not start online master switch when one of connections are running long updates on the current master

具体信息如下：

# /usr/local/bin/masterha_master_switch --master_state=alive --conf=/etc/mha/app1.cnf
 
It is better to execute FLUSH NO_WRITE_TO_BINLOG TABLES on the master before switching. Is it ok to execute on 179.179.19.184(179.179.19.184:)? (YES/no): y
 
Tue Nov  ::  - [info] Executing FLUSH NO_WRITE_TO_BINLOG TABLES. This may take long time..
Tue Nov  ::  - [info]  ok.
Tue Nov  ::  - [info] Checking MHA is not monitoring or doing failover..
Tue Nov  ::  - [info] Checking replication health on 179.179.19.185..
Tue Nov  ::  - [info]  ok.
Tue Nov  ::  - [error][/usr/local/share/perl5/MHA/MasterRotate.pm, ln161] We should not start online master switch when one of connections are running long updates on the current master(179.179.19.184(179.179.19.184:)). Currently  update thread(s) are running.
Details:
{'Time' => '','db' => undef,'Id' => '','User' => 'event_scheduler','State' => 'Waiting on empty queue','Command' => 'Daemon','Info' => undef,'Host' => 'localhost'}
Tue Nov  ::  - [error][/usr/local/share/perl5/MHA/ManagerUtil.pm, ln177] Got ERROR:  at /usr/local/bin/masterha_master_switch line .

分析：set global event_scheduler=off; 主从都要关闭

3. masterha_master_switch 在线切换方面 报错 Got Error: DBI .....failed: Access denied for user

# /usr/local/bin/masterha_master_switch --master_state=alive --conf=/etc/mha/app1.cnf
 
Starting master switch from 179.179.19.185(179.179.:) to 179.179.19.184(179.179.19.184:)? (yes/NO): yes
 
Tue Nov  ::  - [info] Checking whether 179.179.19.184(179.179.19.184:) is ok for the new master..
Tue Nov  ::  - [info]  ok.
Tue Nov  ::  - [info] ** Phase : Configuration Check Phase completed.
Tue Nov  ::  - [info]
Tue Nov  ::  - [info] * Phase : Rejecting updates Phase..
Tue Nov  ::  - [info]
Tue Nov  ::  - [info] Executing master ip online change script to disable write on the current master:
Tue Nov  ::  - [info]   /usr/local/bin/master_ip_online_change_appuanalysis --command=stop --orig_master_host=179.179.19.185 --orig_master_ip=179.179.19. --orig_master_port=--orig_master_user='weixinLX391P_xldbmha' --orig_master_password='weixinLX391P_xldbmha\)qlk' --new_master_host=179.179.19.184 --new_master_ip=179.179.19.184 --new_master_port= --new_master_user='us_mha' --new_master_password='weixinLX391P_xldbmha\)qlk' --orig_master_ssh_user=root --new_master_ssh_user=root
Got Error: DBI connect(';host=179.179.19.184;port=3306;mysql_connect_timeout=4','weixinLX391P_xldbmha',...) failed: Access denied for user 'weixinLX391P_xldbmha'@'179.179.19.166' (using password: YES) at /usr/local/share/perl5/MHA/DBHelper.pm line .
 at /usr/local/bin/master_ip_online_change_app1 line .
 
Tue Nov  ::  - [error][/usr/local/share/perl5/MHA/ManagerUtil.pm, ln177] Got ERROR:  at /usr/local/bin/masterha_master_switch line .

分析：账号密码有需要转移字符的。app1.cnf 文件中user账号相应的密码 password 不能有待转移的字符，例如本例中的')'，但是 账号 repl_user 相应的密码repl_password 没有此限制。

 4.如果使用的是xtrabackup，注意从节点会把event还原上去，可能会造成数据不一致，同步失败的问题。

如果主节点有event，需要手动关闭从节点的event。例如，主节点有归档删除数据的event，从节点需要关闭，否则报错。类似如下错误：

Could not execute Delete_rows event on table ????DB.*****table; Can't find record in '*****', Error_code: 1032; handler error HA_ERR_KEY_NOT_FOUND; the event's master log FIRST, end_log_pos XXXXXXX