Update pid-file, socket, port and datadir in my2.cnf;
Run sudo mysql_install_db --user=mysql --datadir=/var/lib/mysql2;
start the second mysql server with mysqld_safe --defaults-file=/etc/mysql/my2.cnf, then you will have two server running.
Pros and Cons
Easy, use less effort to achieve;
Not good to control, need write a new service command to handle start/stop/etc.
Use mysqld_multi
Steps
Run mysqld_multi --example to show all codes we will use;
Copy and Update mysqld_multi section in my.cnf;
Update group name mysqld to mysqld1(make original instance controlled by mysqld_multi) in my.cnf;
Add new group mysqld2 in my.cnf with user, pid-file, socket, port and datadir.
Run sudo mysql_install_db --user=mysql --datadir=/var/lib/mysql2;
Use command mysqld_multi to manage(start/stop ) all instances.
Pros and Cons
Easy, a little more than the first one;
Easy to control, command mysqld_multi build-in with mysql.
Traps
In MySQL 5.6, when you run mysql_install_db, you might get an error that says FATAL ERROR: Could not find my-default.cnf. Fix it by sudo cp /etc/mysql/my.cnf /usr/share/mysql/my-default.cnf.
You may see [Warning] Can't create test file /var/lib/mysql2/ip-xxx.lower-test, this is because Ubuntu’s security check, Fix it by disable MySQL security check:
Currently, in 2017, the smart home is like mobile phone or pc at 2000, we use DIY computer at that time, but in 2017, we already use brand computer, so smart...
