How to install and start multiple MySQL instances on Windows 2012

Solution 1:

The mistake I was doing was to copy whole MySQL installation folder. You don't need to copy this folder.

  • Simply create a new ini file for each instance that you want to run (examples given above) at any location for e.g. C:\MyInstances\my1.ini.
  • Then create a new folder for e.g. data1 in C:\MyInstances\data1 and copy mysql and information_schema databases in it. You will get these databases from data folder where MySQL is installed. On Windows 2012 (and probably other server OS) it typically is C:\ProgramData\MySQL
  • Then define the following in your ini file.


  1. Then run following command which will install MySQL as service. After services is created simply run the service.

MySqlpath\bin\mysqld --install mysqld1 --defaults-file=PATH_TO_YOUR_INI_FILE

Of course in each ini file, you have to define a different port number as mentioned by @Anthony Fornito.

Solution 2:

I believe you were trying to run them on the same port.

Changed the ports numbers to be different was what made it work

Solution 3:

  1. Create a separate data folder and give FULL CONTROL to NETWORK SERVICE.
  2. Copy the my.ini file to the new data folder.
  3. Create a new file in the data directory called mysql-init.txt and add a single line to ensure that the password of the root user is set.

    • ALTER USER 'root'@'localhost' IDENTIFIED BY '[Enter Password]';
  4. Edit the my.ini file by changing the port, socket, datadir, and shared memory base name. All of which need to be different from other instances of MySQL.



basedir="C:/Program Files/MySQL/MySQL Server 5.7"
  1. From the command line navigate to ~\MySQL Server X.Y\bin\ and run

    • mysqld --install MySQL57-2 --defaults-file=E:\mysql2\data\my.ini --init-file=E:\mysql2\data\mysql-init.txt
  2. Start the service

    • NET START MySQL57-2
  3. Check to make sure the service started successfully. If it didn’t then you can find an error log in the data folder else you should be good to go.