CEMT SET TCPIP

Open or close the CICS® TCP/IP service.

In the CICS Explorer, the Regions operations view provides a functional equivalent to this command.

Description

You can use the SET TCPIP command to open or close CICS internal sockets support.

Note: This command has no effect on the sockets support provided by the TCP/IP for z/OS® CICS Sockets Feature.

Syntax

Press the Clear key to clear the screen. You can start this transaction in two ways:
  • Type CEMT SET TCPIP (or suitable abbreviations for the keywords). The resulting display lists the current status, similar to that obtained by using the CEMT INQUIRE TCPIP command. You can tab to the highlighted or blank fields and overtype them with the required values.
  • Type CEMT SET TCPIP (or suitable abbreviations for the keywords), followed by (value) or ALL, then followed by one or more attribute settings that you want to change. For example, cemt s tcpip status open opens CICS internal sockets support.

Typing ? at the beginning of either the first or second line gives a syntax prompt. Resetting the values takes effect immediately.

CEMT SET TCPIP

Read syntax diagramSkip visual syntax diagramCEMT SET TCPIP( value)ALLOPENCLOSEIMMCLOSEMAXSOCKETS( data-value)

Options

OPENSTATUS
Specifies whether to open or close TCP/IP support, and if TCP/IP support is closed, how the close is done.
OPEN
CICS internal sockets support is opened (that is, new incoming work can be processed, and ongoing work can complete).
Note: If you use CEMT SET TCPIP OPEN to initialize CICS sockets, you must also set TCPIP=YES at CICS initialization by SIT or a SIT override. Otherwise, NOT IN SYSTEM is returned.
CLOSE
CICS internal sockets support is closed. If it is currently open, CICS quiesces all internal sockets activity and then closes any sockets on which CICS is listening for incoming work. Tasks that are using CICS internal sockets are allowed to complete.
IMMCLOSE
CICS internal sockets support is closed. If it is currently open, any tasks that using it are abnormally terminated, and then CICS closes the socket on which CICS is listening for incoming work.
MAXSOCKETS(data-value)
Specifies the maximum number of IP sockets that the CICS sockets domain can manage.

If the userid under which the CICS job is running has superuser authority, the sockets domain can manage up to 65535 sockets.

If the userid under which the CICS job is running does not have superuser authority, the maximum number of sockets that the sockets domain can manage is limited to the number specified in the MAXFILEPROC parameter in SYS1.PARMLIB member BPXPRMxx. If you use the SET SYSTEM command to specify a value greater than that in MAXFILEPROC, CICS resets the limit to the value of MAXFILEPROC. The message MAXFILEPROC LIMIT REACHED is displayed when the request is made.

Note that sockets created by Java™ programs running on threads that are not managed by CICS do not count towards the limit.

If you reduce the limit to less than the number of sockets currently active, CICS prevents new sockets from being created until the number of active sockets falls below the limit.