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MySQL Backup Server (Slave) Gets Fatal Error 1236 from Master When Reading Binary Log on Oracle Big Data Appliance V2 (Doc ID 1595574.1)

Last updated on FEBRUARY 16, 2023

Applies to:

Big Data Appliance Integrated Software - Version 2.0.1 to 2.1.2 [Release 2.0 to 2.1]
Linux x86-64


NOTE: In the examples that follow, user details, cluster names, hostnames, directory paths, filenames, etc. represent a fictitious sample (and are used to provide an illustrative example only). Any similarity to actual persons, or entities, living or dead, is purely coincidental and not intended in any manner.


In the case here the MySQL Backup Server running on Node02 of the cluster reports several conditions which indicate that the MySQL Master Server had crashed and the MySQL Backup Server can not reconnect to the Master.   (Note that on Oracle  Big Data Appliance (BDA) V2 the MySQL Master Server runs on Node03 of the cluster.  The MySQL Backup Server runs on Node02 of the cluster.)  Theses symptoms can be viewed in the MySQL output from "show slave status\G":

Slave_IO_Running: No
Last_IO_Errno: 1236
Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Client requested master to start replication from impossible position'


 Detailed output shows like:

c)  Comparing  the mysql "show slave status\G" output on the MySQL Slave (Node02) with the mysqlbinlog output on the MySQL Master (Node03) indicates an end position on the Master lower than the position on the Slave.  For example:

From the Slave:
Read_Master_Log_Pos: 149749150
Relay_Master_Log_File: mysql-bin.000080
Exec_Master_Log_Pos: 149749150

From the Master:
#1234565 21:07:02 server id 1  end_log_pos 149701932     Xid = 1212345

From this output we see that the end position on the MySQL Master is 149701932, while the MySQL Slave points to a master log far ahead of this i.e. Read_Master_Log_Pos: 149749150.



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