mysql數據不復制，但複製似乎很好

Question

我有一臺4機mysql羣集運行mariadb 10.0.21。我有兩個主人設置，彼此奴役。然後分別從第一個和第二個數據庫中複製兩個只讀的從站。

總之，方法其設置是這樣的：

db1 replicates -> db2 
db1 replicates -> db3 
db2 replicates -> db1 
db2 replicates -> db4 

這是一個非常基本的4 DB設置。

我遇到的問題是我設置了一個nagios用戶來監視第一個數據庫上的集羣。

我檢查了一下，我可以登錄前3個數據庫，但沒有第4個與nagios用戶。我可以這樣做，而不是在每個數據庫上創建nagios用戶，因爲我在前兩臺數據庫機器上覆制了我的mysql數據庫。

但由於某種原因，nagios用戶從來沒有在db4上創建，就像在db2上一樣，即使複製在所有節點上看起來都不錯。

正如你可能還記得，我有db 2複製到第四分貝。

如果我做DB 2顯示主人身份，我可以看到我複製MySQL數據庫：

MariaDB [mysql]> show master status; 
+--------------------+----------+------------------------------+------------------+ 
| File    | Position | Binlog_Do_DB     | Binlog_Ignore_DB | 
+--------------------+----------+------------------------------+------------------+ 
| mariadb-bin.000078 |  376 | jfwiki,jokefire,bacula,mysql |     | 
+--------------------+----------+------------------------------+------------------+ 
1 row in set (0.00 sec) 

如果我檢查Nagios的用戶有2號分貝，它是。

MariaDB [mysql]> select User,Host,Password from user where user like 'nagios'; 
    +--------+-------------+-------------------------------------------+ 
    | User | Host  | Password         | 
    +--------+-------------+-------------------------------------------+ 
    | nagios | 52.4.204.96 | *somepasswordhash       | 
    +--------+-------------+-------------------------------------------+ 
    1 row in set (0.00 sec) 

此用戶並未在db2上創建，但由於複製而存在。

如果我檢查DB4從屬地位，複製似乎完全沒問題：

[root@db4:~] #mysql -e "show slave status\G" | egrep "Slave_IO_State|Master_Host|Slave_IO_Running|Slave_SQL_Running|Last_Errno|Seconds_Behind_Master" 
       Slave_IO_State: Waiting for master to send event 
        Master_Host: db2.example.com 
      Slave_IO_Running: Yes 
      Slave_SQL_Running: Yes 
        Last_Errno: 0 
     Seconds_Behind_Master: 0 

如果我檢查的DB4 Nagios的用戶的存在我在DB2上做的方式，用戶只需ISN 「T有：

MariaDB [mysql]> select User,Host from user where user like 'nagios'; 
Empty set (0.00 sec) 

所以我的問題是，爲什麼Nagios的用戶不會複製到DB從DB1的方式一樣 - > DB2和DB1 - > DB3？即使在db4上從屬複製似乎沒問題？我可以使用監控主機中的nagios用戶登錄所有主機。

下面是從複製命令對DB4全力輸出的情況下，我錯過了什麼，從我的grep前面：

MariaDB [(none)]> show slave status\G 
*************************** 1. row *************************** 
       Slave_IO_State: Waiting for master to send event 
        Master_Host: db2.example.com 
        Master_User: jf_slave 
        Master_Port: 3306 
       Connect_Retry: 60 
       Master_Log_File: mariadb-bin.000078 
      Read_Master_Log_Pos: 376 
       Relay_Log_File: db4-relay-bin.000044 
       Relay_Log_Pos: 537 
     Relay_Master_Log_File: mariadb-bin.000078 
      Slave_IO_Running: Yes 
      Slave_SQL_Running: Yes 
       Replicate_Do_DB: 
      Replicate_Ignore_DB: 
      Replicate_Do_Table: 
     Replicate_Ignore_Table: 
     Replicate_Wild_Do_Table: 
    Replicate_Wild_Ignore_Table: 
        Last_Errno: 0 
        Last_Error: 
       Skip_Counter: 0 
      Exec_Master_Log_Pos: 376 
       Relay_Log_Space: 1121 
       Until_Condition: None 
       Until_Log_File: 
       Until_Log_Pos: 0 
      Master_SSL_Allowed: Yes 
      Master_SSL_CA_File: /opt/mysql/ca.crt 
      Master_SSL_CA_Path: 
       Master_SSL_Cert: /opt/mysql/db4.example.com.crt 
      Master_SSL_Cipher: 
       Master_SSL_Key: /opt/mysql/db4.example.com.key 
     Seconds_Behind_Master: 0 
Master_SSL_Verify_Server_Cert: No 
       Last_IO_Errno: 0 
       Last_IO_Error: 
       Last_SQL_Errno: 0 
       Last_SQL_Error: 
    Replicate_Ignore_Server_Ids: 
      Master_Server_Id: 2 
       Master_SSL_Crl: /opt/mysql/ca.crt 
      Master_SSL_Crlpath: 
        Using_Gtid: No 
        Gtid_IO_Pos: 
1 row in set (0.00 sec) 

我看到在DB4的MariaDB的日誌中的一些錯誤，但是他們沒有什麼不同比我在nagios用戶數據複製成功的前3個數據庫上看到的錯誤要多。

151004 15:34:36 [Note] Error reading relay log event: slave SQL thread was killed 
151004 15:34:36 [ERROR] Error reading packet from server: Lost connection to MySQL server during query (server_errno=2013) 
151004 15:34:36 [Note] Slave I/O thread killed while reading event 
151004 15:34:36 [Note] Slave I/O thread exiting, read up to log 'mariadb-bin.000078', position 376 
151004 15:36:47 [Note] Slave SQL thread initialized, starting replication in log 'mariadb-bin.000078' at position 376, relay log './db4-relay-bin.000042' position: 537 
151004 15:36:47 [Note] Slave I/O thread: connected to master 'jf_slave@db2.example.com:3306',replication started in log 'mariadb-bin.000078' at position 376 
151007 4:24:12 [Note] Error reading relay log event: slave SQL thread was killed 
151007 4:24:12 [ERROR] Error reading packet from server: Lost connection to MySQL server during query (server_errno=2013) 
151007 4:24:12 [Note] Slave I/O thread killed while reading event 
151007 4:24:12 [Note] Slave I/O thread exiting, read up to log 'mariadb-bin.000078', position 376 
151007 4:28:20 [Note] Slave SQL thread initialized, starting replication in log 'mariadb-bin.000078' at position 376, relay log './db4-relay-bin.000043' position: 537 
151007 4:28:20 [Note] Slave I/O thread: connected to master 'jf_slave@db2.example.com:3306',replication started in log 'mariadb-bin.000078' at position 376 

那麼爲什麼會有這種數據庫不一致，當所有的複製指標看起來好嗎？爲什麼nagios用戶不能以第一個3分貝的方式登錄到db4？

感謝

Answer 1

因爲你需要設置Log_slave_updates在每個服務器上的CNF文件。