Multiple DB2 subsystems with one TCP/IP stack

The TCP Server Bind Control allows multiple DB2® subsystems to use the same port number within the same z/OS® image.

This allows multiple DB2 subsystems that bind to any IP address (also known as INADDR_ANY in sockets API terms) and the same port number on the same stack to be bound to separate IP addresses. For example, consider two DB2 subsystems in a data sharing group where both have the same LOCATION and same DRDA PORT. A new 'BIND ipaddr' parameter is added to the PORT statement. When DB2 (identified by job name ssnmDIST) issues a bind to the port number in the PORT statement and to INADDR_ANY, the bind is restricted to the IP address specified on the PORT statement for that DB2 subsystem. This allows two DB2 subsystems to share the same stack by limiting them to different single IP addresses (virtual IP addresses are recommended). This allows them to be reached by any physical connectivity that can get to the stack.