How to run 2 MySQL versions in the same machine ?

At least the following options must be different for each server:


port=port_num

port controls the port number for TCP/IP connections.


socket=path

socket controls the Unix socket file path on Unix and the name of the named pipe on Windows. On Windows, it is necessary to specify distinct pipe names only for those servers that support named-pipe connections.



pid-file=file_name

This option is used only on Unix. It indicates the pathname of the file in which the server writes its process ID.



Following article will help you to run several servers on one machine

[url]http://dev.mysql.com/doc/refman/5.0/en/multiple-unix-servers.html
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Here is a quick way to do the installation

1) Install the first MySQL server by following steps given in INSTALL_BINARY
Note : Soft link should be set to

ln -s full-path-to-mysql-VERSION-OS mysqlServer1


2) Start the server in the port you wish. You need to specify the path to


$ mysqld_safe --socket=file_name --port=port_number


e.g= fileName=/tmp/mysqlServer1.sock

3) Install the second server. Set the soft link as "mysqlServer2"

4) Start the server in the port you wish with socketFile Name


$ mysqld_safe --socket=/tmp/mysqlServer2.sock --port=3309