To keep this simple, for both MySQL and Postgres I will assume that you have already setup your master to have a user that can access everything that is needed for replication and that there is nothing in the network that would prevent your hosts from talking to each other.
I ran into a problem the other day where I was running an ETL job that plays a shell game with tables.
In both MySQL and Postgres there are times when you will want to login to the server in an automated non-interactive fashion.
The ~/.psqlrc file allows you to specify session level settings consistently to be used when you connect to Postgres via the command line.
MySQL In MySQL you can run “show processlist;” or “show full processlist;” to get a list of all of the queries that are running on the system and how long they have been running.
It is always advised to restrict permissions for connections to the minimal amount that they need to perform their function.