Configuring TCP/IP

The TCP/IP stack on your local machine should already be correctly configured. Contact your system administrator if you encounter problems.

Verifying the TCP/IP installation

To verify that the CICS® Universal Client can communicate with CICS servers, use the TCP/IP PING command to check the route to the CICS server:
        ping [machine address | name]
To start PING, enter a command like the following:
        ping 192.113.36.200 
where 192.113.36.200 is the IP address of your CICS server. If you are using a Domain Name Server (DNS), you can specify the symbolic host name rather than the IP address of the server.
If the statistics message shows a value other than 0% packet loss, it is possible that TCP/IP is not correctly configured:
  • Check for TCP/IP definition errors.
  • Check the physical connection to the network.

The PING command differs slightly, depending on your operating system. For more information, refer to the documentation supplied with your operating system.

Refer to TCP/IP settings for information on TCP/IP settings.

Configuring TCP/IP on CICS Transaction Server for z/OS

CICS Universal Client can send ECI requests over TCP/IP to CICS Transaction Server for z/OS® V2.2 and later. To perform this configuration:
  1. Set the SIT parameter TCPIP=YES.
  2. Install the following:
    • CICS-supplied transient data queue CIEO, in group DFHDCTG
    • Transaction CIEP in group DFHIPECI
    • Program DFHIEP in group DFHIPECI
  3. Define the TCP/IP address and host name for the z/OS system. By default they are defined in the PROFILE.TCPIP and TCPIP.DATA data sets.
  4. Add a TCP/IP listener to CICS. Use the following CEDA command to define a TCPIPSERVICE in a group:
    CEDA DEF TCPIPSERVICE(service-name) GROUP(group-name)
    Ensure that the group in which you define the service is in the startup GRPLIST, so that the listener starts when CICS is started. Key fields are explained as follows:
    POrtnumber
    The port on which the TCP/IP service listens.
    PRotocol
    The protocol of the service is ECI.
    TRansaction
    The transaction that CICS runs to handle incoming ECI requests. Set it to CIEP.
    Backlog
    The number of TCP/IP requests that are queued before TCP/IP starts to request incoming requests.
    Ipaddress
    The IP address (in dotted decimal form) on which the TCPIPSERVICE listens. For configurations with more than one IP stack, specify ANY to make the TCPIPSERVICE listen on all addresses.
    SOcketclose
    Whether CICS should wait before closing the socket after issuing a receive for incoming data on that socket. NO is recommended for ECI connections, to ensure that the connection from the Client daemon always remains open.
    ATtachsec
    Specifies the level of attach-time security required for TCP/IP connections.
  5. Use the following command to install the TCPIPSERVICE definition:
    CEDA INS TCPIPSERVICE(service-name) GROUP(group-name)

Next steps

  1. Use the Configuration Tool to create a server definition; see The Configuration Tool interface.
  2. Configure the server definition; see Configuring Server settings.