MySQL1236错误的恢复

从库出现问题

mysql> show slave status\G;
*************************** . row ***************************
               Slave_IO_State:
                  Master_Host: 192.168.220.141
                  Master_User: rep
                  Master_Port:
                Connect_Retry:
              Master_Log_File: mysql-bin.000005               I/O线程当前正在读取的主服务器二进制日志文件的名称
          Read_Master_Log_Pos: 764                            在当前的主服务器二进制日志中，I/O线程已经读取的位置
               Relay_Log_File: relay-bin.000018               SQL线程当前正在读取和执行的中继日志文件的名称
                Relay_Log_Pos: 4                              在当前的中继日志中，SQL线程已读取和执行的位置
        Relay_Master_Log_File: mysql-bin.000005               由SQL线程执行的包含多数近期事件的主服务器二进制日志文件的名称
             Slave_IO_Running: No
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB: mysql
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0                             最后的错误号，0表示没有错误
                   Last_Error: 　　　　　　　　　　　　　　　　　 最后错误的描述
                 Skip_Counter: 0                             最近被使用的用于SQL_SLAVE_SKIP_COUNTER的值
          Exec_Master_Log_Pos: 764                           来自主服务器的二进制日志的由SQL线程执行的上一个时间的位置（Relay_Master_Log_File）。在主服务器的二进制日志中的(Relay_Master_Log_File,Exec_Master_Log_Pos)对应于在中继日志中的(Relay_Log_File,Relay_Log_Pos)
              Relay_Log_Space: 107　　　　　　　　　　　　　     所有原有的中继日志结合起来的总大小　　　
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos:
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master: NULL
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 1236
                Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file'
               Last_SQL_Errno:
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id:
 row in set (0.00 sec)

ERROR:
No query specified

mysql> 

查看mysql的错误日志

　　大致的意思就是说，从库不能读取主库的binlog日志文件了，造成这种故障的原因可能是：

1. 　　　　从库不能连接主库
2. 　　　　主库的binlog日志被删除了

　　　　　　.......

[root@mysql ~]# tail /data//mysql.err          //查看错误日志
 :: [Note] Slave SQL thread initialized, starting replication in log 'mysql-bin.000005' at position , relay log '/data/3307/relay-bin.000018' position:
 :: [ERROR] Error reading packet from server: Could not find first log file name in binary log index file ( server_errno=)
 :: [ERROR] Slave I/O: Got fatal error  from master when reading data from binary log: 'Could not find first log file name in binary log index file', Error_code:
 :: [Note] Slave I/O thread exiting, read up to log 'mysql-bin.000005', position
[root@mysql ]# ping 192.168.220.141              //测试和主库的连通性
PING 192.168.220.141 (192.168.220.141) () bytes of data.
 bytes from 192.168.220.141: icmp_seq= ttl= time=0.197 ms
 bytes from 192.168.220.141: icmp_seq= ttl= time=0.029 ms
 bytes from 192.168.220.141: icmp_seq= ttl= time=0.025 ms
^C
--- 192.168.220.141 ping statistics ---

查看主库的日志

Slave I/O thread exiting, read up to log 'mysql-bin.000005', position 764提示读取mysql-bin.000005错误，查看主库的binlog日志后发现没有mysql-bin.0000005日志文件
这是因为长时间没有开启数据库，binlog的存活时间是7天，所以binlog00000005日志应该是被删除了
规定binlog日志存活时间的参数在my.cnf中
expire_logs_days = 7        //单位是天，0表示不自动删除

[root@mysql ~]# ll /data//
total
drwxr-xr-x  mysql mysql   Nov  : data
-rw-r--r--  mysql mysql   Oct  : my.cnf
-rwx------  root  root    Oct  : mysql
-rw-rw----  mysql mysql    Nov  : mysql-bin.
-rw-rw----  mysql mysql     Nov  : mysql-bin.index
srwxrwxrwx  mysql mysql      Nov  : mysql.sock
-rw-r-----  mysql root   Nov  : mysql_oldboy3306.err
-rw-rw----  mysql mysql      Nov  : mysqld.pid
[root@mysql ~]# 

调整从库的同步位置：

change master to master_log_file='mysql-bin.000006',master_log_pos=4

mysql> stop slave;
Query OK,  rows affected (0.00 sec)

mysql> change master to master_log_file='mysql-bin.000006',master_log_pos=4;
Query OK,  rows affected (0.32 sec)

mysql> start slave;
Query OK,  rows affected (0.00 sec)

mysql> show slave status\G;
*************************** . row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.220.141
                  Master_User: rep
                  Master_Port:
                Connect_Retry:
              Master_Log_File: mysql-bin.
          Read_Master_Log_Pos:
               Relay_Log_File: relay-bin.
                Relay_Log_Pos:
        Relay_Master_Log_File: mysql-bin.
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB: mysql
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno:
                   Last_Error:
                 Skip_Counter:
          Exec_Master_Log_Pos:
              Relay_Log_Space:
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos:
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master:
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0                  //没有IO错误了
                Last_IO_Error:
               Last_SQL_Errno:
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id:
 row in set (0.00 sec)

ERROR:
No query specified

mysql>