How can I check and add/change the servers' linking?
I remember adding some permissions inside the database.
In the "mysql.mysql" databse of the master server, there are several tables which conatin the permission records for the mysql users that connect from the slaves. The records exist for the hostname of the slave server and for the IP address for the slave server. Search all tables in the "mysql" database for the old hostname and old IP address and replace them with the new hostname and new ip address. Then do a "flush privileges;" in mysql or restart mysql. On the slave server there are no changes reqzired unless the IP or hostname of the master server changes.
Some debug instriction which can be used to check if the slave is able to connect to the master again are here: