The following questions are offered as a starting point to assist in narrowing the scope of the problem.

1. Are there any special or unusual operating circumstances?

   • Is this a new application?

   • Are new procedures being used?

   • Are there recent changes that might be affecting the system? For example, have any of the software products or applications been changed since the application or scenario last ran successfully?

   • For application programs, what application programming interface (API) was used to create the program?

   • Have other applications that use the software or communication APIs been run on the user's system?

   • Has a fix pack recently been installed? If the problem occurred when a user tried to use a feature that had not been used (or loaded) on their operating system since it was installed, determine IBM's most recent fix pack and load it after installing the feature.

2. Has this error occurred before?

   • Are there any documented resolutions to previous error conditions?

   • Who were the participants and can they provide insight into a possible course of action?

3. Have you explored using communications software commands that return information about the network?

   • TCP/IP might have valuable information retrieved from using TCP/IP commands and daemons.

4. Is there information returned in the SQLCA (SQL communication area) that can be helpful?

   • Problem handling procedures should include steps to examine the contents of the SQLCODE and SQLSTATE fields.

   • SQLSTATEs allow application programmers to test for classes of errors that are common to the DB2^® family of database products. In a distributed relational database network this field might provide a common base.

5. Was DB2START executed at the Server? Additionally, ensure that the DB2COMM environment variable is set correctly for clients accessing the server remotely.

6. Are other machines performing the same task able to connect to the server successfully? The maximum number of clients attempting to connect to the server might have been reached. If another client disconnects from the server, is the client who was previously unable to connect, now able to connect?

7. Does the machine have the proper addressing? Verify that the machine is unique in the network.

8. When connecting remotely, has the proper authority been granted to the client? Connection to the instance might be successful, but the authorization might not have been granted at the database or table level.

9. Is this the first machine to connect to a remote database? In distributed environments routers or bridges between networks might block communication between the client and the server. For example, when using TCP/IP, ensure that you can PING the remote host.

Parent topic: Troubleshooting