Modifying the change log inventory job for using TCP/IP

The PORT parameter specifies TCP/IP port number that DDF uses to accept incoming DRDA connection requests. The RESPORT parameter specifies the TCP/IP port number that DDF uses to accept incoming DRDA 2-phase commit resynchronization requests. The values for these parameters must be decimal numbers between 0 and 65534, where 0 indicates that TCP/IP support is being deactivated. The non-zero value for PORT must not be the same as the non-zero value for RESPORT.

You can also specify the SECPORT parameter, to specify the secure port that accepts incoming TCP/IP connection requests from remote DRDA clients that use secure SSL protocol. If the SECPORT parameter specifies the same value as the PORT parameter, the TCP/IP port accepts only secure TCP/IP connection requests. For more information, see Configuring the Db2 server for SSL.

Db2 uses the resync port only for transaction completion states after failures, so no user data or authentication protocols are ever exchanged on the resync port. You can enable SSL security for the resync port by defining a network policy on all Db2 requesters and Db2 servers.

For data sharing, all members of the Db2 data sharing group must have the same value for PORT. RESPORT must be uniquely assigned to each Db2 member so that no two Db2 members use the same TCP/IP port for 2-phase commit resynchronization. The PORT and RESPORT parameters can be changed on any Db2 member by running the utility change log inventory. After running the utility, you must stop and then restart Db2. Because PORT is the same for all members of the Db2 group, this process must be repeated on every member of the group when PORT is changed.

If you use dynamic VIPA to support a Parallel Sysplex® environment, specify the Db2 group dynamic VIPA on the TCP/IP PORT statement for the DRDA port number.

You can define an alias location for all or selected members of a data sharing group by using the ALIAS parameter.

Remember, a zero value for either PORT or RESPORT is the same as deactivating TCP/IP support in Db2.

You can also specify an IPv4 address and an IPv6 address for the subsystem in the DDF statement of the change log inventory utility (DSNJU003). Specifying an IPv4 and an IPv6 address keeps the subsystem IP addresses constant, regardless of the z/OS system where the subsystem is started. The IP address moves with the Db2 subsystem. In data sharing environments, a constant IPv4 address and a constant IPv6 address can be assigned to represent the entire group.