Select this option to access the database server using DRDA over TCP/IP.
To access a database server using DRDA over TCP/IP, QMF for Windows or QMF for WebSphere must be able to establish a TCP/IP connection from the local host to the remote host and remote port. QMF for Windows or QMF for WebSphere requires a WinSock 1.1 (or later) interface for the installed TCP protocol stack.
Use your TCP/IP networking staff and your TCP/IP software vendor's technical support services to implement and support your network configuration.
Type the IP address of the machine housing the database.
If you enter a TCP domain name for the host name, QMF for Windows Administrator resolves the name to an address using the GetHostByName socket call. Otherwise, you can specify the host in dotted decimal notation (such as, 172.16.37.33).
Type the TCP/IP port number for the database server. The port number is the port that DB2 is assigned to listen for DRDA TCP/IP conversations.
Select one of the following options if you do not know the port number to use on DB2 UDB for z/OS.
LOCATION=DB2PDDF LUNAME=DB2PDDF PASSWORD=(NULL) GENERICLU=(NULL) PORT=NULL RPORT=NULL
,--------------------------------------------,SDSF OUTPUT DISPLAY DB2DMSTR ,COMMAND INPUT ===>, 19.24.18 STC01839 DSNL004I - DDF START COMPLETE LOCATION DB2DDDF LU FFX1.DB2DDDF GENERICLU -NONE DOMAIN -NONE TCPPORT 0 RESPORT 0
In these two examples the TCPPORT has been set to zero. This is the de-activated state and it indicates that DB2 DRDA is not listening on any port.
Follow these steps to update your BSDS to set this port to 446 for DB2 to start listening, then run the Change Log Inventory utility to change this status:
DDFPORT 446
PORT 446 TCP OMVS ; DRDA port for DB2D
DB2 should respond to your request.
The default port for DB2 to listen for DRDA TCP/IP conversations on the iSeries is 446. The default port can already be assigned, but it might not be active. Or, the default port may have been changed to another value. If so, you receive the WSAECONNREFUSED error message when QMF for Windows tries to connect.
Verify Listen State for iSeries
Follow these steps to verify whether the DRDA port is in a listen state:
Follow these steps to ensure that the DDM server (which opens the DRDA port) will autostart when the STRTCP command is issued during system startup:
Type the name of the relational database (RDB) server that you are configuring in the SDF. The RDB name is not visible to end-users.
Platform | RDB Name |
---|---|
DB2 z/OS, OS390, and MVS(TM) | Location name |
DB2 Universal Database or DB2 Common Server | Database name |
iSeries | Database name in the iSeries Relational Database Directory |
If you do not know what value to enter, run the following query at the server (you can use any table if SYSIBM.SYSTABLES does not exist):
SELECT DISTINCT CURRENT SERVER FROM SYSIBM.SYSTABLES
The returned value is the RDB name for the database server.
The RDB name is the name of the database that is taken from the iSeries Relational Database Directory Entry. Type the following command to locate the RDB name:
DSPRDBDIRE
Specify the codepage to use with the ANSI version of QMF for Windows. The default codepage is the Windows CCSID.
Specify the codepage to use with the Unicode version of QMF for Windows. The default codepage is UTF-8 (1208).
Check this check box to use load balancing to maintain a balanced connection to the database server.
In DB2, load balancing distributes processing and communications activity evenly across a network so that no single device is overwhelmed. Load balancing is frequently used for networks where it is difficult to predict the number of requests that will be issued to a server.
QMF for Windows supports DB2 database servers that use load balancing. By checking Enable load balancing for DB2 database servers that support load balancing, QMF for Windows will receive a list of network addresses that can be used as alternatives after the initial connection to the DB2 database server is made. Subsequent connections can use one of the addresses returned by DB2. These addresses are not necessarily the same address that is configured in the SDF, but they will connect to the same set of database tables.
If you enable load balancing, and the DB2 supports this feature, QMF for Windows receives a list of IP addresses with rankings as to how often it wants to be connected to each address. QMF for Windows takes this list and goes to a specific IP address for its first connection. Next, it will go to the next address, then to the third address, and so on. If an IP address is busy or not working, load balancing will go to another address. This balances the load on each address and provides multiple addresses if the first address cannot be used.