Disconnecting from CICS

To disconnect the Db2 attachment to CICS®, you can do an orderly disconnection or a forced disconnection.

About this task

Begin general-use programming interface information. Orderly termination is recommended whenever possible. An orderly termination of the connection allows each CICS transaction to terminate before thread subtasks are detached. Therefore, no indoubt units of recovery should exist when you reconnect.

Forced termination is not recommended, but at times you might need to force the connection to end. A forced termination of the connection can abnormally terminate CICS transactions that are connected to Db2. Therefore, indoubt units of recovery can exist at reconnect.

Procedure

To disconnect CICS with an orderly termination, use one of the following methods:
- Enter the DSNC STOP QUIESCE command. CICS and Db2 remain active.
  For example, the following command stops the Db2 subsystem (QUIESCE) allows the currently identified tasks to continue normal execution, and does not allow new tasks to identify themselves to Db2:
```
-STOP DB2 MODE (QUIESCE)
```
  The following message appears when the stop process starts and frees the entering terminal (option QUIESCE):
```
DSNC012I THE ATTACHMENT FACILITY STOP QUIESCE IS PROCEEDING
```
  When the stop process ends and the connection is terminated, the following message is added to the output from the CICS job:
```
DSNC025I THE ATTACHMENT FACILITY IS INACTIVE
```
- Enter the CICS command CEMT PERFORM SHUTDOWN. During program list table (PLT) processing, the CICS attachment facility is also named to shut down. Db2 remains active. For information about this command, see CICS shutdown.
- Enter the Db2 command CANCEL THREAD. The thread terminates abnormally.
To disconnect CICS with a forced termination, use one of the following methods:
- Enter the DSNC STOP FORCE command. This command waits 15 seconds before detaching the thread subtasks and in some cases can achieve an orderly termination. This message appears when the stop process starts and frees the entering terminal (option FORCE):
```
DSNC022I THE ATTACHMENT FACILITY STOP FORCE IS PROCEEDING
```
  Db2 and CICS remain active.
- Enter the CICS command CEMT PERFORM SHUTDOWN IMMEDIATE. For information about this command, see CICS shutdown.
- Enter the Db2 command STOP DB2 MODE (FORCE). CICS remains active.
A forced termination also occurs in the following situations:
- A Db2 abend occurs. CICS remains active.
- A CICS abend occurs. Db2 remains active.
- STOP is issued to the Db2 or CICS attachment facility. The CICS transaction overflows to the pool. The transaction issues an intermediate commit. The thread is terminated at commit time, and further Db2 access is not allowed.
When the stop process ends and the connection is terminated, the following message is added to the output from the CICS job:
```
DSNC025I THE ATTACHMENT FACILITY IS INACTIVE
```