SET MODENAME

Change the number of sessions in an APPC session group.

SET MODENAME

Conditions: INVREQ, NOTAUTH, SYSIDERR

For more information about the use of CVDAs, see CICS-value data areas (CVDAs).

Description

The SET MODENAME command enables you to increase or decrease the number of sessions available (bound) in a session group on a particular APPC connection. You identify the group to be changed by the MODENAME and CONNECTION values in its SESSIONS definition, rather than the name of the SESSIONS definition. You need both values because MODENAMEs are not necessarily unique across connections.

SET MODENAME applies only to parallel session groups on an APPC connection on which CICS is already in session with its partner system, and only to groups created with a SESSIONS resource definition (not to SNASVCMG LU services manager sessions). The changes last only until the connection is released or the number of sessions is changed again.

If you increase the number of sessions, you can specify whether or not CICS should acquire the additional sessions; if you decrease the number, CICS unbinds the excess sessions automatically. If more than the target number of sessions are in use at the time of the command, CICS allows activity to quiesce before unbinding. Tasks using a session on the connection are allowed to complete, but new tasks requiring a session are not started until activity drops below the new limit.

Note: CICS uses a task that executes LU Services Manager transaction CLS1 to acquire or release sessions on parallel-session APPC connections. Data is passed to the task in a temporary storage queue whose name begins with the default prefix of DF. If your system defines queues named starting with DF as recoverable, CICS cannot initiate this task until a subsequent commit on the part of the task that issued the SET MODENAME command (either a SYNCPOINT command or an implicit syncpoint).

Options

ACQSTATUS(cvda)

specifies either that additional sessions are to be acquired if the AVAILABLE value increases the number, or that the number of available sessions is to be set to zero. CVDA values are:

ACQUIRED: Additional sessions, if any, are to be acquired.
CLOSED: The number of sessions is to be set to zero. CLOSED is equivalent to specifying AVAILABLE (0) and should not be specified with AVAILABLE. This value prevents either of the connected systems from using a session in the group.

AVAILABLE(data-value)

specifies, as a halfword binary value, the number of sessions to be available for use at any one time. The range for this value is from zero to the MAXIMUM value specified in the SESSIONS definition; you can determine this limit, if necessary, with an INQUIRE MODENAME command.

CONNECTION(data-value)

specifies the 4-character name of the connection for which this group of sessions is defined (from the CONNECTION value value in the SESSIONS definition).

MODENAME(data-value)

specifies the 8-character MODENAME value of the group of sessions that you are modifying (from its SESSIONS definition).

Conditions

INVREQ

RESP2 values:

3: MODENAME ‘SNASVCMG’ was specified.
4: The AVAILABLE value is out of range.
5: AVAILABLE was specified but CICS is not in session on this connection.
6: CLOSED was specified with AVAILABLE.
7: ACQSTATUS has an invalid CVDA value.
8: This is not a parallel-session APPC group.
9: ACQUIRED was specified but CICS is not in session on this connection.

NOTAUTH

RESP2 values:

100: The user associated with the issuing task is not authorized to use this command.

SYSIDERR

RESP2 values:

1: The connection cannot be found.
2: The MODENAME within the connection cannot be found.