Automate Dead Letter Handler using Triggering

How to Automate Dead Letter Handler Mechanism using Triggering setup.

Make Inter communication between the 2 Queue managers (example A & B).

Change Destination Queue manager DEADQ(DEADQ)

ALTER QMGR DEADQ(DEADQ)

Create a local queue and assign SYSTEM.DEAD.LETTER.QUEUE attributes.

DEFINE QLOCAL (DEADQ) LIKE(SYSTEM.DEAD.LETTER.QUEUE)

Dead Letter Handler Techniques:

Scenario 1: Configuring the DLQ Handler as a server service object.

If the receiver channel is not able to put the message in the destination queue, then those messages are

be placed in the DLQ of the remote WebSphere MQ queue manager, provided a DLQ is defined for it.

The DLQ Handler is kept waiting for incoming messages on the DLQ. You specify the DLQ to accept

undelivered messages using the queue manager menu option Properties => Default dead queue. For

example, in Figure 1, the name of the DLQ for undelivered messages for the IBMQMR queue manager is specified as DEADQ:

1.      Check the Dead Letter queue is presented or Not.

To run the DLQ handler as a service, you need to define a server service object in that queue manager. This example uses a batch file and rules table for the DLQ Handler.

2.      Create dlqhandler.bat and copy the below details into the file and copy this file into D:\MQ\ dlqhandler.bat

cd "C:\Program Files\IBM\WebSphere MQ\bin"

runmqdlq %1 %2 %3 %4 

Ex: 

The rules table should be defined with some REASON and ACTION sequence and WAIT (YES), which means that the DLQ Handler waits indefinitely for further messages to arrive on the DLQ

Rule Table Definition:

RULETBL.RUL:

The content of rule table definition:

INPUTQ('DEADQ') INPUTQM(A) RETRYINT(45) WAIT(YES)

REASON(MQRC_Q_FULL) ACTION(FWD) FWDQ(BLOCAL) FWDQM(B)

Listing 3  Define server service object for DLQ Handler.

DEFINE SERVICE(dlqhandler) +

SERVTYPE(SERVER) +

CONTROL(MANUAL) +

STARTCMD('C:\IBM\WebSphere\MQ\dlqhandler.bat') +

DESCR('dead letter queue handler as server service') +

STARTARG('DEADQ IBMQMR < C:\IBM\WebSphere\MQ\RULETBL.RUL') +

STDOUT('C:\IBM\WebSphere\MQ\Log.txt') +

STDERR('C:\IBM\WebSphere\MQ\Err.txt') +

REPLACE

The value of STARTCMD is the absolute path of the executable file dlqhandler.bat (on Windows), asshown above in the Listing 3. After you have defined the server service object for the DLQ Handler, you  need to make sure that group id mqm, user id MUSR_MQADMIN (on Windows) has Read andExecutable privileges on the dlqhandler.bat executable file. RULETBL.RUL is the rules table file.

And start the service command and monitor the service status. 

Scenario 2: Triggering the DLQ Handler

Scenario 2 involves setting up the WebSphere MQ trigger facility so that the DLQ Handler runs andprocesses undelivered messages only when they arrive on the DLQ. To set up Scenario 2, define aprocess object processdlq within the queue manager B that is triggered whenever the trigger conditions are met. Specify the absolute path of the program or process to be triggered in the Application ID field, to avoid unexpected results in the DLQ with the message.

Create a Process definition:

Create a process definiton with name of PROCESSDLQ and keep the applicid as below.

Create a bat file called dlq_trigger.bat and copy it to D:\MQ path.

cd "C:\Program Files\IBM\WebSphere MQ\bin"

runmqdlq < RULETBL.RUL

Rule table should like below:

INPUTQ('DEADQ') INPUTQM(B) RETRYINT(45) WAIT(NO)

REASON(MQRC_Q_FULL) ACTION(FWD) FWDQ(DLQX) FWDQM(B)

Set the Triggering feature ON on this DEADQ of the IBMQMR queue manager, so that whenever amessage arrives on DEADQ, DLQ Handler becomes active to handle the message based on thecontents of the rules table file RULETBL.RUL. Specify the process name to be triggered as processdlq and the initiation queue as SYSTEM.DEFAULT.INITIATION.QUEUE:

DEFINE QLOCAL(DEADQ) DESCR('WebSphere MQ Default Dead Letter Queue')

INITQ(SYSTEM.DEFAULT.INITIATION.QUEUE) TRIGTYPE(EVERY) TRIGGER PROCESS('processdlq')

1 : DEFINE QLOCAL(DEADQ) DESCR('WebSphere MQ Default Dead Letter Queue')

INITQ(SYSTEM.DEFAULT.INITIATION.QUEUE) TRIGTYPE(EVERY) TRIGGER PROCESS('processdlq')

AMQ8006: WebSphere MQ queue created.

:

DISPLAY QLOCAL(DEADQ) DESCR INITQ TRIGGER TRIGTYPE PROCESS

2 : DISPLAY QLOCAL(DEADQ) DESCR INITQ TRIGGER TRIGTYPE PROCESS

AMQ8409: Display Queue details.

QUEUE(DEADQ) TYPE(QLOCAL)

DESCR(WebSphere MQ Default Dead Letter Queue)

INITQ(SYSTEM.DEFAULT.INITIATION.QUEUE)

TRIGGER PROCESS(processdlq)

TRIGTYPE(EVERY)

Listing 9. Run the trigger monitor using the command prompt.

runmqtrm -m IBMQMR -i SYSTEM.DEFAULT.INITIATION.QUEUE

            Listing 10. Definition and status of the trigger monitor server service object

display svstatus('triggerdlq') all

1 : display svstatus('triggerdlq') all

AMQ8632: Display service status details.

SERVICE(triggerdlq) STATUS(RUNNING)

PID(9540) SERVTYPE(SERVER)

STARTDA(2011-12-27) STARTTI(17.11.53)

CONTROL(MANUAL)

STARTCMD(C:\Program Files\IBM\WebSphere MQ\bin\runmqtrm)

STARTARG(-m IBMQMR) STOPCMD( )

STOPARG( ) DESCR(trigger the dlq handler)

STDOUT(C:\IBM\WebSphere\MQ\Log_runmqtrm.txt)

STDERR(C:\IBM\WebSphere\MQ\Err_runmqtrm.txt)