hlq.PROFILE.TCPIP data set

You define the CICS® region to TCP/IP on z/OS® in the hlq.PROFILE.TCPIP data set (described in z/OS Communications Server: IP Configuration Reference and z/OS Communications Server: IP Configuration Guide). In it, you must provide entries for the CICS region in the PORT statement, as shown in Figure 1.

The format for the PORT statement is:

         port_number TCP CICS_jobname

Write an entry for each port that you want to reserve for an application. Figure 1 shows two entries, allocating port number 3000 for SERVA, and port number 3001 for SERVB. SERVA and SERVB are the job names of our CICS regions.

These two entries reserve port 3000 for exclusive use by SERVA and port 3001 for exclusive use by SERVB. The listener transactions for SERVA and SERVB should be bound to ports 3000 and 3001 respectively. Other applications that want to access TCP/IP on z/OS are prevented from using these ports.

Ports that are not defined in the PORT statement can be used by any application, including SERVA and SERVB if they need other ports.

Figure 1. Definition of the hlq.TCP/IP profile

 ;
 ; hlq.PROFILE.TCPIP
 ; ===================
 ;
 ; This is a sample configuration file for the TCPIP address space.
 ; For more information about this file, see "Configuring the TCPIP
 ; Address Space" and "Configuring the Telnet Server" in the 
 ; Customization and Administration Manual.
        ..........
        ..........
 ; ----------------------------------------------------------------------
 ; Reserve PORTs for the following servers.
 ;
 ; NOTE:  A port that is not reserved in this list can be used by
 ;        any user.  If you have TCP/IP hosts in your network that
 ;        reserve ports in the range 1-1023 for privileged
 ;        applications, you should reserve them here to prevent users
 ;        from using them.
 PORT
        ..........
        ..........
   3000 TCP SERVA            ; CICS Port for SERVA              1
   3001 TCP SERVB            ; CICS Port for SERVB

Two different CICS listeners running on the same host can share a port. See the discussion on port descriptions in z/OS Communications Server: IP Configuration Reference for more information about ports.