The MySQL database is replaced by MariaDB 5.5 in Red Hat Enterprise 7,
which is compatible with MySQL 5.5 but it is not compatible with MySQL 5.0.
See the information about found incompatibilities below. It is expected that
you will need to modify and apply your configuration files on the new machine
manually. However, some backed up configuration files might be modified already
to avoid issues caused by some known incompatibilities. Only configuration
files are backed up. All the other important files (e.g. certificates) have to be
backed up manually.

You can find more at: [link:https://access.redhat.com/articles/2123151]


