GTID环境中手动修复主从故障一例（Error 1236/Error 1396）
Preface
I got an replication error 1236 when I modified the password of a user without starting slave threads of replication.Further more,the user was absent in slave.below is the whole operation how I solve the issue.
Procedure
I modified the user password on master at first.
root@localhost:mysql3306.sock [(none)]>alter user zlm@'192.168.56.%' identified by 'zlmzlm';
Query OK, rows affected (0.00 sec)
I then started the slave replication on zlm3.
#mysql -uroot -p -S /var/lib/mysql/mysql.sock
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is
Server version: 5.7.-log MySQL Community Server (GPL) Copyright (c) , , Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. root@localhost:mysql.sock [(none)]>start slave;
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>show slave status\G
*************************** . row ***************************
Slave_IO_State:
Master_Host: 192.168.56.100
Master_User: repl
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: No //The IO_Thread is not running on account of Error 1236
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:
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno:
Last_IO_Error: Got fatal error from master when reading data from binary log: 'The slave is connecting using CHANGE MASTER TO MASTER_AUTO_POSITION = 1, but the master has purged binary logs containing GTIDs that the slave requires.'
Last_SQL_Errno:
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id:
Master_UUID: 2a4b3562-2ab6-11e8-be7a-080027de0e0e
Master_Info_File: /data/mysql/mysql3306/data/master.info
SQL_Delay:
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count:
Master_Bind:
Last_IO_Error_Timestamp: ::
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set: 27af30ca--11e8-ad7e-080027de0e0e:-,
2a4b3562-2ab6-11e8-be7a-080027de0e0e:- //This is the id of maximum transaction executed on slave.
Auto_Position:
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
row in set (0.00 sec)
I decided to set gtid_purged variable to a certain value.So I executed "reset master;" to remove the value of "Executed_Gtid_Set".
root@localhost:mysql.sock [(none)]>reset master;
Query OK, rows affected (0.05 sec) root@localhost:mysql.sock [(none)]>show slave status\G
*************************** . row ***************************
Slave_IO_State:
Master_Host: 192.168.56.100
Master_User: repl
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: No
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:
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno:
Last_IO_Error: Got fatal error from master when reading data from binary log: 'The slave is connecting using CHANGE MASTER TO MASTER_AUTO_POSITION = 1, but the master has purged binary logs containing GTIDs that the slave requires.'
Last_SQL_Errno:
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id:
Master_UUID: 2a4b3562-2ab6-11e8-be7a-080027de0e0e
Master_Info_File: /data/mysql/mysql3306/data/master.info
SQL_Delay:
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count:
Master_Bind:
Last_IO_Error_Timestamp: ::
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set: //The value has been cleared after operation of "reset master;".
Auto_Position:
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
row in set (0.00 sec)
In order to know which value of "gtid_purged" I should set,I analyzed the binlog on master.
zlm@192.168.56.100: [(none)]>show master status;
+------------------+----------+--------------+------------------+-------------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------------------------------------+
| mysql-bin. | | | | 2a4b3562-2ab6-11e8-be7a-080027de0e0e:- |
+------------------+----------+--------------+------------------+-------------------------------------------------+
row in set (0.00 sec) zlm@192.168.56.100: [(none)]>flush logs;
Query OK, rows affected (0.04 sec) zlm@192.168.56.100: [(none)]>show master status;
+------------------+----------+--------------+------------------+-------------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------------------------------------+
| mysql-bin. | | | | 2a4b3562-2ab6-11e8-be7a-080027de0e0e:- |
+------------------+----------+--------------+------------------+-------------------------------------------------+
row in set (0.00 sec) [root@zlm1 :: /data/mysql/mysql3306/logs]
#mysqlbinlog -vv --base64-output=decode-rows mysql-bin. > /root/.log
[root@zlm1 :: /data/mysql/mysql3306/logs]
#cd [root@zlm1 :: ~]
#ls -l|grep .log
-rw-r--r-- root root Jul : .log
[root@zlm1 :: ~]
#less .log
... /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at
# :: server id end_log_pos CRC32 0x6e71f8f2 Start: binlog v , server v 5.7.-log created :: at startup
ROLLBACK/*!*/;
# at
# :: server id end_log_pos CRC32 0x074cfb08 Previous-GTIDs
# 2a4b3562-2ab6-11e8-be7a-080027de0e0e:-
# at
# :: server id end_log_pos CRC32 0x9125f364 GTID last_committed= sequence_number= rbr_only=no
SET @@SESSION.GTID_NEXT= '2a4b3562-2ab6-11e8-be7a-080027de0e0e:12715627'/*!*/;
# at
# :: server id end_log_pos CRC32 0x7a5353bf Query thread_id= exec_time= error_code=
SET TIMESTAMP=/*!*/;
SET @@session.pseudo_thread_id=/*!*/;
SET @@session.foreign_key_checks=, @@session.sql_auto_is_null=, @@session.unique_checks=, @@session.autocommit=/*!*/;
SET @@session.sql_mode=/*!*/;
SET @@session.auto_increment_increment=, @@session.auto_increment_offset=/*!*/;
/*!\C utf8 *//*!*/;
SET @@session.character_set_client=,@@session.collation_connection=,@@session.collation_server=/*!*/;
SET @@session.lc_time_names=/*!*/;
SET @@session.collation_database=DEFAULT/*!*/;
ALTER USER 'zlm'@'192.168.56.%' IDENTIFIED WITH 'mysql_native_password' AS '*512FB3FAA6F522E351929CAC70AD8EBB0F5901B6'
/*!*/;
# at
# :: server id end_log_pos CRC32 0x0882ea24 Rotate to mysql-bin. pos:
SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/;
DELIMITER ;
# End of log file //I've known that the operation of altering password is in the uuid:12715627.Therefore,I could set gtid_purged to the previous gtid(uuid:5-12715626).
I tried to set "gtid_purged" to the right value according to the content of binlog on master.
root@localhost:mysql.sock [(none)]>set @@global.gtid_purged='2a4b3562-2ab6-11e8-be7a-080027de0e0e:5-12715626';
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>start slave io_thread;
Query OK, rows affected (0.01 sec) root@localhost:mysql.sock [(none)]>show slave status\G
*************************** . row ***************************
Slave_IO_State:
Master_Host: 192.168.56.100
Master_User: repl
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: No //It was not running again.
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:
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno:
Last_IO_Error: Got fatal error from master when reading data from binary log: 'The slave is connecting using CHANGE MASTER TO MASTER_AUTO_POSITION = 1, but the master has purged binary logs containing GTIDs that the slave requires.'
Last_SQL_Errno:
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id:
Master_UUID: 2a4b3562-2ab6-11e8-be7a-080027de0e0e
Master_Info_File: /data/mysql/mysql3306/data/master.info
SQL_Delay:
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count:
Master_Bind:
Last_IO_Error_Timestamp: ::
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set: 2a4b3562-2ab6-11e8-be7a-080027de0e0e:-
Auto_Position:
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
row in set (0.00 sec) root@localhost:mysql.sock [(none)]>reset master;
Query OK, rows affected (0.03 sec) root@localhost:mysql.sock [(none)]>set @@global.gtid_purged='2a4b3562-2ab6-11e8-be7a-080027de0e0e:1-12715626'; //I began with the first gtid this time.
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>stop slave;
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>start slave;
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>show slave status\G
*************************** . row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.56.100
Master_User: repl
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 //IO_Thread could work normally.
Slave_SQL_Running: No //SQL_Thread was down instead.
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: //A new arrival error 1396 occurred.
Last_Error: Error 'Operation ALTER USER failed for 'zlm'@'192.168..%'' on query. Default database: ''. Query: 'ALTER USER 'zlm'@'192.168..%' IDENTIFIED WITH 'mysql_native_password' AS '*512FB3FAA6F522E351929CAC70AD8EBB0F5901B6''
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno:
Last_IO_Error:
Last_SQL_Errno:
Last_SQL_Error: Error 'Operation ALTER USER failed for 'zlm'@'192.168..%'' on query. Default database: ''. Query: 'ALTER USER 'zlm'@'192.168..%' IDENTIFIED WITH 'mysql_native_password' AS '*512FB3FAA6F522E351929CAC70AD8EBB0F5901B6''
Replicate_Ignore_Server_Ids:
Master_Server_Id:
Master_UUID: 2a4b3562-2ab6-11e8-be7a-080027de0e0e
Master_Info_File: /data/mysql/mysql3306/data/master.info
SQL_Delay:
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State:
Master_Retry_Count:
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp: ::
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set: 2a4b3562-2ab6-11e8-be7a-080027de0e0e:
Executed_Gtid_Set: 2a4b3562-2ab6-11e8-be7a-080027de0e0e:-
Auto_Position:
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
row in set (0.00 sec) root@localhost:mysql.sock [(none)]>ALTER USER 'zlm'@'192.168.56.%' IDENTIFIED WITH 'mysql_native_password' AS '*512FB3FAA6F522E351929CAC70AD8EBB0F5901B6'; //I couldn't executed it in mysql cli either.
ERROR (HY000): Operation ALTER USER failed for 'zlm'@'192.168.56.%'
root@localhost:mysql.sock [(none)]>
Then,I checked the user on both master and slave.I found that there was no "zlm" user on slave at all.
//Master
root@localhost:mysql3306.sock [(none)]>select user,host from mysql.user;
+---------------+--------------+
| user | host |
+---------------+--------------+
| repl | 192.168..% |
| zlm | 192.168..% |
| bkuser | localhost |
| mysql.session | localhost |
| mysql.sys | localhost |
| root | localhost |
+---------------+--------------+
rows in set (0.00 sec) //Slave
root@localhost:mysql.sock [(none)]>select user,host from mysql.user;
+---------------+--------------+
| user | host |
+---------------+--------------+
| repl | 192.168..% |
| bkuser | localhost |
| mysql.session | localhost |
| mysql.sys | localhost |
| root | localhost |
+---------------+--------------+
rows in set (0.00 sec) root@localhost:mysql.sock [(none)]>create user zlm@'192.168.56.%'; //I created the absent user "zlm" on slave.
Query OK, rows affected (0.00 sec) root@localhost:mysql.sock [(none)]>start slave sql_thread;
Query OK, rows affected (0.01 sec) root@localhost:mysql.sock [(none)]>show slave status\G
*************************** . row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.56.100
Master_User: repl
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 //It was ok.
Replicate_Do_DB:
Replicate_Ignore_DB:
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:
Last_IO_Error:
Last_SQL_Errno:
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id:
Master_UUID: 2a4b3562-2ab6-11e8-be7a-080027de0e0e
Master_Info_File: /data/mysql/mysql3306/data/master.info
SQL_Delay:
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count:
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set: 2a4b3562-2ab6-11e8-be7a-080027de0e0e:
Executed_Gtid_Set: 27af30ca--11e8-ad7e-080027de0e0e:, //This gtid was generated by the statment of "create user ... ".
2a4b3562-2ab6-11e8-be7a-080027de0e0e:- //The executed gtid was equal with the master.
Auto_Position:
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
row in set (0.00 sec)
Summary
- Error 1236 is common phenomenon in our replication of MySQL which always due to lack of specific binlog files.
- Before you execute a statement on master.You'd better start your slave replication at first.Obviously it means our test environment.
- If you were not sure which transaction was stuck.Analyze the binlog file is always a good idea to solve these kind of issues.
- In my case,I know clearly about what I've operated in master.So I can easily execute the same operation on slave.But the product environment is complecated and it's not recommended to do so.
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