z/OS® V2R1 Communications Server provides support to create a VIPARANGE DVIPA with affinity to the address space of the application that created it. In previous releases, the SIOCSVIPA and SIOCSVIPA6 IOCTL functions and the MODDVIPA utility supported the define and delete options. In z/OS V2R1 Communications Server, a new define with affinity option is supported. When an application uses the SIOCSVIPA or the SIOCSVIPA6 IOCTL function to create a DVIPA with the address space affinity option, connection requests for this DVIPA are routed to a server that runs in the address space of the application. This behavior is beneficial when there are multiple shareport applications listening on the IPv4 inaddr_any or the IPv6-unspecified address. With this new support, the application that created the DVIPA is preferred over other listeners. If no matching listeners are available, normal shareport load balancing is used to select the best available listener.
To enable the affinity for application-instance DVIPAs function, perform the appropriate tasks in Table 1.
| Task | Reference |
|---|---|
| To create a VIPARANGE DVIPA with affinity using the SIOCSVIPA or SIOCSVIPA6 ioctl, issue the IOCTL command by using the new DVR_DEFINE_AFFINITY option instead of using DVR_DEFINE. | Using the SIOCSVIPA or SIOCSVIPA6 ioctl command in z/OS Communications Server: IP Configuration Guide |
| To create a VIPARANGE DVIPA with affinity by using the MODDVIPA utility, issue the MODDVIPA command with the new -a option instead of using the -c option. | Using the MODDVIPA utility in z/OS Communications Server: IP Configuration Guide |