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Quick Beginnings for DB2 Extended Enterprise Edition for UNIX

Setting the DB2COMM Registry Value

Your DB2 server can support multiple communication protocols concurrently; however, you only need to enable the protocols that you want to use.

If you deselected a detected protocol during installation, or have added a communication protocol to your network since installation, you must update the db2comm registry value with the protocol that you now want to support.

The db2comm registry value determines which protocol's connection managers will be enabled when the database manager is started. You can set this value for multiple communication protocols by separating the keywords with commas.

For your DB2 server, DB2COMM can be any combination of the following keywords:

starts APPC support

starts IPX/SPX support

starts TCP/IP support


To avoid problems with the Control Center and the Client Configuration Assistant, ensure that DB2COMM is set in the DB2 registry. It is not recommended that you use any other mechanism to set the DB2COMM value.

To set the db2comm registry value for the current instance, enter the db2set DB2COMM=protocol_names command. Change the protocol_names parameter to reflect those protocols that you want to start when the database manager is started.

For example, to set the database manager to start connection managers for the APPC and TCP/IP communication protocols, enter:

   db2set DB2COMM=appc,tcpip


If you are setting up communications for the Administration Server, use the db2set command as follows:

   db2set DB2COMM=appc,tcpip -i DB2DAS00
   db2admin stop
   db2admin start


The name of the Administration Server's instance. If you are not sure of the Administration Server name, enter the following command to view it:

When the db2start command is reissued, connection managers for the protocols specified by the db2comm registry value are started.

Figure hint not displayed.

If there are problems starting a protocol's connection managers, a warning message is displayed and the error messages are logged in the db2diag.log file, located in the instance directory.

Additionally, any failure encountered while executing the db2start command is logged to a time-stamped file in the log subdirectory within the instance directory. This file contains the db2start results from each database partition server in the instance.

If there is no error when the db2start command is run, these files are removed.

Refer to the Troubleshooting Guide for information on the db2diag.log file.

If db2comm is undefined or set to null, no protocol connection managers are started when the database manager is started.

For more information on setting DB2 parameters, see "Controlling the DB2 Profile Registry".


You are now ready to configure the server workstation to use any of the following communication protocols:

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