I need some clarification on how (some) JDBC drivers connect to (Informix) Databases.
We had the issue of "connection refused" when trying to connect to Informix connection manager from a Java application via JDBC,although access was granted via firewall.
When we consulted Informix Team,they told us we need also access to Informix database servers,since connection manager only returns the IP of the DB server to connect.And yes,after getting access to two additional database servers that we are not referring to in our application,it started working.I have checked the Informix documentation and below is the related statement:
When a client application makes a connection request through a redirect-mode SLA, the Connection Manager returns a database server's IP address and port number to the client application. The client application then uses the information to connect to the specified database server. Connection Manager redirection takes place in the communication layer, so additional action is not required by client applications
This is the part not clear to me.Can JDBC driver react to the manager and try to connect again with the returned IP and portNumber? What does it mean "Connection Manager redirection takes place in the communication layer"? How can this be handled in OSI layer?