Connection Process

Most problems arise during the initial connection of the JDBC client to the database. For this reason, we shall first completely describe the steps that occur during the connection process, and mention some common problems that can arise.

Step 1. Loading the HP Driver for JDBC Class Files

If this step fails, the most likely cause is that the Java CLASSPATH environment variable has not been set correctly.
Other possible causes include the driver files not being installed, or unreadable or corrupt driver files.

Step 2. Loading the Network Components

If this step fails, it could mean a bad network connection, or the client not being connected to the network.

Step 3. Loading the Specified Server Name

If this step fails, the most likely cause is either an incorrect or invalid server name, an unreachable server (network down, or outside firewall), or a down server. The user can try to use other methods to reach the server such as ping, telnet, or ftp.

Step 4. Connecting to the 31700 or the Specified Port Number

If this step fails, it means that there either was no process listening on that port number, or something other than the JDBC Monitor was listening on that port number. A server administrator can verify that the JDBC Monitor process is running and accepting connections on the default or other port number.

Step 5. Validating the Userid and Password

If this step fails, the most likely cause is an incorrect userid, or invalid passwords for the userid. You can attempt to use ftp or telnet to verify that the userid and passwords are valid.

Step 6. Spawning a Server Process by the JDBC Monitor

If this step fails (some resource limit is reached on the server), the monitor logs should indicate the reason for the failure.

Step 7. Switching to the Effective User

Once the process is spawned, the monitor switches the effective user id to the user that was supplied in the user validation. This ensures that the user only has the privileges assigned to the user. If this step fails, the most likely cause is that the monitor was not started by "root," the superuser for HP-UX, or a user with the PM capabilities for MPE/iX. The user can log on to the server and verify that the monitor process was started by the correct user and has the proper capabilities.

Step 8. Executing the JDBC Server by the Spawned Process

If this process fails, the JDBC Server executable could be corrupt, have incorrect permissions, be missing, or be incompatible to the server operating system (installed components for incorrect platform). The user can log on to the server and manually verify the server installation files.

Step 9. Attempting to Connect to the Specified Database

If this step fails, the client should receive an ALLBASE/SQL error message through the java.sql.SQLException that is shown. Common causes of this failing are incorrect database name or a corrupt database. Make sure the case-sensitivity of the database name is also checked.

If all the preceding steps are successful, the Driver Manager will return a connection to the database.

Connection Process

Technical documentation

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