Starting the system

Using the HMCS console for initialization

The HMCS console can be used to IPL z/OS. Use of the system console or NIP consoles defined in HCD is not required when using HMCS consoles to IPL. If the HMCS console is not available, z/OS looks in the IODF for devices to be used as NIP consoles.

Using the MCS console for initialization

In HCD, you can specify a list of device numbers to use as NIP consoles. The initialization programs use the first online and ready device in the list. NIP consoles must be devices that are locally connected to the system using control units that do not support systems network architecture (SNA) protocols. This means that SMCS consoles cannot be used as NIP consoles. If that device is also specified on a CONSOLE statement in CONSOLxx, it is initialized as an MCS console and appears to change to an MCS console when console initialization is complete. If no NIP consoles are defined, or no NIP consoles are online when MVS™ is loaded, MVS tries to use the system console during initialization.

Using the system console for initialization

If neither the HMCS or MCS console is available, the system console is used to initialize the system. The system console is located on the Hardware Management Console (HMC), where you load the system software and specify the LOAD parameter. Then you use this console to initialize the system. The initialization programs might require setting initial values, specifying an alternate master catalog, and setting the time and date.