Bug #53989 "RESET SLAVE" cannot clear Master_user option
Submitted: 26 May 2010 10:51 Modified: 27 May 2010 6:25
Reporter: Libing Song Email Updates:
Status: Not a Bug Impact on me:
None 
Category:MySQL Server: Replication Severity:S3 (Non-critical)
Version:mysql-trunk-merge OS:Any
Assigned to: CPU Architecture:Any

[26 May 2010 10:51] Libing Song 
Description:
On 5.1, RESET SLAVE resets the value of Master_user as the default user.
But it don't reset the value of Master_user on 5.5

How to repeat:
source include/master-slave.inc;
connection slave;
source include/slave_stop.inc;
change master to master_user='test';
show slave status;
reset slave;
show slave status;
[27 May 2010 6:25] Sveta Smirnova 
Thank you for the report.

According to http://dev.mysql.com/doc/refman/5.5/en/reset-slave.html:

In MySQL 5.4—unlike the case in MySQL 5.1 and earlier—RESET SLAVE no longer changes replication connection parameters such as master host, master port, master user, and master password. (This means that START SLAVE can be issued without requiring a CHANGE MASTER TO  statement following RESET SLAVE.) 

This means this is intended behavior.