AppendixF.Diagnosing DB2 Connectivity Problems

Appendix F. Diagnosing DB2 Connectivity Problems

Figure F.1 illustrates what happens when you issue a CONNECT TO database statement. It also shows how the system database, node, and DCS directories are used during the process.

Figure F.1. Database connection flowchart

For example, when the CONNECT TO SAMPLE statement is issued, DB2 first looks for the database alias SAMPLE in the system database directory. This is the alias used for the database with the name MYSAMPLE. If the alias is not found, you get an SQL1013N error. If it is found, DB2 checks if this is a local or remote database. If it is a local database, DB2 initiates a connection to the database MYSAMPLE. If it is a remote database, DB2 checks the node directory to retrieve information about the remote server and then initiates a connection to the server.

The flowchart in Figure F.1 shows what is involved to establish a database connection. Follow this chart to diagnose connection problems more easily.