This document describes how to set up the External Call Interface (ECI) within CICS. It covers the following topics:
Important:
If the terms and concepts in this document are unfamiliar to you, ask an appropriate CICS system programmer. Only authorized
personnel should make changes to mainframe computer systems.
The DFH$SOT group contains three TCP/IP services. For our
purposes, the pertinent service is ECI. The ECI service has, defined in it, the
TCP/IP port number through which the CICS region listens to the ECI. By
default, IBM predefines the TCP/IP port number as
"1435". If this port is already reserved for another
CICS region, you may have to define a different port number in the ECI service.
For more information, see your IBM documentation.
You must specify SOCKETCLOSE(NO) on the
TCPIPSERVICE. If you need to specify a timeout
for a task initiated using ECI over TCP/IP, specify an RTIMOUT
value on the mirror transaction. Note that the standard mirror,
CPMI, is defined with profile DFHCICSA, which
specifies RTIMOUT(NO). This means that long running mirrors will
wait indefinitely for data, unless you specify a different
RTIMOUT for the mirror transaction.
To define an ECI service without security
Use CEDA ALTER to supply the ECI TCPIPService with a unique TCP/IP port number.
Use CEDA ALTER to set the ECI ATTACHSEC to "LOCAL"
To define an ECI service with security
Copy the ECI TCPIPService to an ECIS TCPIPSERVICE.
Use CEDA ALTER to supply the ECIS TCPIPSERVICE with a unique TCP/IP port number.
Use CEDA ALTER to set the ECIS ATTACHSEC to "VERIFY".
A successful installation should pass the following verification tests:
CEMT INQUIRE TCPIPSERVICE(*) should now display your services with status OPE. A status of CLO might indicate an already used (not unique) TCP/IP port
number.
CEMT I TCPIPSERVICE(ECI) to verify TCPIPSERVICE in CICS.
CEMT I TRA(CIEP) to verify transaction CIEP in CICS.
CEMT I PROGRAM(DFHIEP) to verify program DFHIEP in CICS.
CEMT I TRAN(CPMI) to verify transaction CPMI in CICS.
CEMT I PROGRAM(DFHMIRS) to verify program DFHMIRS in CICS.
CEMT I TD(CIEO) to verify program TQ queue CIEO.
Verify that the groups DFHISC DFHDCTG and DFHIPECI are added to the active autoinstall.
Tip:
You can check the mentioned programs and transactions and TD queues by using CEMT INQUIRE TCPIPSERVICE(*).
This table describes the handling of errors in the CICS ECI connection or the RPC Server for CICS ECI.
| Problem | Handling |
|---|---|
| A CICS program sends abend code in response. | The CICS session is closed and the next call opens a different session. |
The TCP/IP connection is lost with a SocketTimeoutException.
|
The CICS session is closed and the next call opens a different session. |
The TCP/IP connection is lost with an EOFException.
|
|