I have had many problems creating a second connection using the Client Configuration Assistant since version 6 of DB/2. Through research, here is what I have found to be the cause.

When a connection is created to a DRDA database, three separate entities are created (catalogued).

1. Node
2. Database
3. DCS database

These all three relate to each other.

The Node basically specifies the IP address (for TCPIP nodes).
The Database refers to the Node and the DCS database (local name) and can have an alias.
The DCS database is required because of the connection to a DRDA database. It refers to the real database (in our case TSDDB2P), but not the Node.

For some reason, whenever you use the Client Configuration Assistant to revise the properties of the connection, the Client Configuration Assistant attemps to perform the following updates:
1. Changes the Node name (not significant because it seems to handle this properly).
2. Changes the DCS database local name to the first letter (e.g. T) of the DCS database (e.g. TSDDB2P).
3. Changes the Database name (not alias) to match the DCS database local name (e.g T as described in 2).

This presents a problem in our environment since we connect to two different databases that both start with the letter 'T'. When the Client Configuration Assistant creates this duplicate Database name the changes must be cancelled and all connection information is lost. Otherwise the following error message persists:

The update database operation failed.

SQL1317N The local database name already exists in the Database Connection Services directory.

For additional information, press the help button. Correct the problem described in the help message and retry.

Here is the work-around that I have come up with for our situtation:
Use command line scripts to create the connections and then update the ODBC and connection information via the Windows ODBC connection manager.

Has anyone else experienced this? Are there any other solutions known? Is anyone aware of a fix for this Client Configuration Assistant bug?