MySQL does not start - Ubuntu 14.04 LTS after migration to new disk
You only changed the ownership and permissions for the mysql datadir, not all the files below it. You should apply those changes recursively with the -R option.

I would do it this way:

$ sudo chown -R mysql:mysql /media/juanjo/2d4aef3c-ae2e-4b30-8bb7-c5723eb5403b/mysql-db-new/mysql

$ sudo chmod -R g+rwX /media/juanjo/2d4aef3c-ae2e-4b30-8bb7-c5723eb5403b/mysql-db-new/mysql


The datadir doesn't need to be other-accessible.



Also make sure that the full chain of directories above (/media/juanjo/2d4aef3c-ae2e-4b30-8bb7-c5723eb5403b/mysql-db-new/) are readable &amp; executable by mysql:mysql.