It is very important that the CCIAPPC module be able to determine the Local LU to use for communication with the Host application. You may have configured everything else correctly and all of your other APPC applications may work, but if you miss this final step you will fail to establish a CCI session with the host application. If the CCI-INITCLIENT call returns CCI error 9 and CCI_GETERROR returns the message "CCIAPPC failed to allocate an APPC session, ensure that Local LU is defined" it is likely that you have failed to complete this final step. When CCIAPPC attempts to allocate an LU 6.2 session with the remote system it must specify the Remote LU name which it requires a session with. This is the Remote LU name specified in the CCI Servername parameter (e.g. the /S parameter in FHREDIR.CFG). However, APPC needs to know the Local LU name as well as the Remote LU name when attempting to establish a session between the LUs.
To enable APPC to retrieve the Local LU name to use when attempting to allocate APPC sessions set the APPCLLU environment variable to the Local LU Name prior to starting the CCIAPPC client.
For Example:
SET APPCLLU=CCILLU01