How to insert or update PCHIDs

Here are the detailed steps you need to perform to insert or update PCHIDs in a validated work IODF.

1. Create a validated work IODF with one of the two methods described in Build a production IODF. Your validated work IODF may lack at least one PCHID that you need to insert or may contain obsolete PCHIDs that you want to update.
2. Go back to the Activate or Process Configuration Data menu shown in Figure 87 and use task Build IOCP input data set to export the I/O configuration from the validated work IODF to an IOCP data set (with PCHIDs still missing or obsolete). The hardware configuration token is passed with the IOCP statements (TOK keyword). This token is used to assure that during the process of assigning PCHID values the contents of the IODF is not changed.

   Download this IOCP data set to the workstation where the CMT is running.

3. Use the CHPID Mapping Tool with the downloaded IOCP data set. For information on how to use the CHPID Mapping Tool, refer to the online help and the related documentation.

   The output of a successful CMT run is again an IOCP data set which contains the original I/O definitions together with inserted and/or updated PCHID values. The original hardware configuration token is still contained in the generated statements.

4. Upload the new IOCP data set to the host and use the HCD primary task Migrate configuration data to import the PCHIDs from the updated IOCP data set into the validated work IODF. During this task, you select
   migrate option ---> 3. PCHIDs
   
   from Figure 132 in Migrating input data sets using the HCD dialog.

   When importing these statements into the validated work IODF via the migration process for PCHID migration, HCD verifies that the token passed with the IOCP statements match the token stored in the IODF. If this is the case, and if the logical I/O definition described by the imported IOCP statements does not differ from the IODF data, HCD writes the PCHID values into the IODF. If the token does not match, for example, because the IODF has been updated in the meantime, a PCHID migration will not be performed. In this case you must start the process from the beginning.

   Note:

   The IOCP input data set may contain keyword values which exceed the 255 character limitation of the assembler program used by HCD for parsing the IOCP statements. This may be the case for the PARTITION (PART) keywords on the RESOURCE statement and on the CHPID statements for spanned channel paths. The affected I/O configuration statements must be deleted in order to perform a successful PCHID migration. However, note that the High Level Assembler V1.5 removes the 255 character limitation.
5. If a PCHID migration has been successfully done, you can invoke the Build Production IODF task (again). HCD now builds a production IODF that contains all the data that is required to write the I/O configuration data set (IOCDS) via the IOCP program to the Support Element (SE) of the machine, ready to be used for the next IML.

To support the algorithm of mapping the logical CHPID definitions to physical channels, a CMT user can specify priorities to the control units (CU priorities). It is possible to preserve these values across different invocations of the CMT. For this purpose, the CMT passes the CU priorities as special comments to HCD. HCD takes these comment lines and stores them in the IODF attached to the corresponding processor. When generating an IOCP input file for the CMT, HCD includes these comments into the generated statements. HCD does not make these comments visible in the HCD dialog or in the reports.