Creating an IOCDS source file for a new CPC

All logical partitions, channel paths, control units, and I/O devices must be defined in the IOCDS source file to generate an IOCDS, which can then be used to perform power-on reset of the CPC.

Create an IOCDS source file as part of the installation procedure for a new CPC.

Use the text editor of your choice to create a file with the statements for the logical partitions, channel paths (chpids), control units, and I/O devices.
To create IOCP input statements:
  1. Create a drawing of the physical arrangement of control units and attached devices to show all channel connections. You can use your own floor plan or some other source. It is much easier to be certain you have included all of the I/O devices on your system in the IOCP statements when you can see where all of the devices are. For more information about floor plans, see the Installation Manual for Physical Planning for your CPC (for example, for IBM z16 Model A01, see the 3931 Installation Manual for Physical Planning, GC28-7015).
  2. Enter the statements. Use IOCP statements and functions and List of I/O devices and control units for specific information, and observe the following tips:
    • Enter the ID statement first. The first eight characters of the MSG1 parameter are the IOCDS name displayed on the Hardware Management Console when the IOCDS is built. Make certain the SYSTEM parameter matches your system.
    • Enter the RESOURCE statement. Define each logical partition and logical channel subsystem.
    • Enter the UUID statement if you want to enable UUID checking for any logical partitions.
    • Enter the CHPID statements. Define each physical channel path installed on your system.
    • Enter the CNTLUNIT statements. It is important to match the PROTOCL and UNITADD parameters with the values set in each control unit by the system installer.
    • Enter the IODEVICE statements
    • Enter the FUNCTION statements.

After completing the input, save the edited file and exit the editor.

Use another CPC running an operating system version of IOCP (z/OS®, z/VM®, or z/VSE®) to verify the card-image input statements for this IOCDS source file. If you do not have access to an operating system version of IOCP capable of verifying an IOCDS source file, ask your service representative to verify the IOCDS source for you.

If you are upgrading to a CPC whose SYSTEM= value supports execution parameter CHECKCPC=NO, write the IOCDS for the new CPC on your current CPC using CHECKCPC=NO. See Machine rules to determine which CPCs can write an IOCDS in preparation for an upgrade and which CPCs can have an IOCDS written to them by ICP IOCP. Inform the service representative which IOCDS to use after the upgrade.

If you are not upgrading or cannot write an IOCDS in preparation for the upgrade, use a utility available to your personal computer and operating system to download the IOCDS source file to USB flash memory drive. Source from a flash memory drive can be in VFAT or DOS file formats or have been compressed. The IOCDS source file you create must be available to the new CPC installer at the time the new CPC is installed. Instead of a USB flash memory drive, you can import an uncompressed IOCP source file to the SE from an FTP location.