At the same time on a machine there must not be a second server that is using the same port number.
So if you want to use the same port number for old NMDDB and new NMDDB you must temporarily switch the port of one of this services during data migration
To migrate metadata it's recommended to have two MySQL services running on the same machine. If there are no firewall restriction you can run services also on different machines.
service #1 - is the service where the new meta-database is installed - it has to run in federated mode.
service #2 - is the service where the old meta-database is installed - it may also run in federated mode.
use database niota_mdv20 as your working/migration database.
stop MySQL service where your metadata are located if it's not running with “–federated” option
start MySQL service with “–federated” option
open a MySQL client and connect as “root” to the MySQL server of the new (target) release
open script to create a database to read data from the old (source) release
check if database was created successfully
open script to create federated server
run script to create federated server
open script to create federated tables to read data from the source release
run script to create federated tables
check if tables are created and data can be retrieved for every table
open script to run migration procedure
run migration procedure for every group of metadata tables