After preparing NetView® or a similar package, use the hardware configuration definition (HCD) to interactively define your I/O configuration changes. (Use of the HCD is described more fully in the MVS™ library.)

To attach a device to the system:

1. Physically attach the device.
2. Define the device to MVS using HCD.
3. Activate the new configuration using the MVS command ACTIVATE IODF.

MVS then issues message IOS502I, which causes NetView to start the IOS502I command list. The IOS502I command list calls the ISTDEFIN command list for each device added to the system.