MySQL Bugs: #70056: mysql_upgrade does not support mysqld

Bug #70056	mysql_upgrade does not support mysqld_multi environments
Submitted:	16 Aug 2013 3:05
Reporter:	Ben Krug	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: C API (client library)	Severity:	S3 (Non-critical)
Version:	5.5, 5.6	OS:	Linux
Assigned to:		CPU Architecture:	Any
Tags:	mysql_upgrade, mysqld_multi

Description:
mysql_upgrade does not support mysqld_multi environments.  It ignores [mysqld_multi] and [mysqln].  To add insult to injury, mysql_upgrade no longer supports datadir options, so to upgrade, you have to do it manually, instance-by-instance, and create temporary my.cnf files for each instance, one at a time, to specify datadir.  Further, since mysql_upgrade calls mysqlcheck and the mysql client, these temporary my.cnf files also need settings for [mysql_upgrade], [mysqlcheck] and [mysql] to specify socket and port for each, and datadir and user for mysql_upgrade.

How to repeat:
set up an environment with multiple mysql instances and mysqld_multi.  Try to upgrade.

Suggested fix:
Update mysql_upgrade script to check for mysqld_multi and [mysqln] groups, and act accordingly.