If you have not already done so, define the communications control unit
for the z/OS host, such as the 3172 or the 3745 control unit, to z/OS. Use
either an z/OS configuration program (MVSCP) or a hardware configuration definition
(HCD), depending on the version of your z/OS system:
- When using a version earlier than z/OS 4.1.0, use an MVSCP.
- When using a version of z/OS 4.1.0 or later, use an HCD or an MVSCP.