MQSeries.net :: View topic - Duplicate message?

MQSeries.net

Tech Exchange

Education

Certifications

Library

Info Center

SupportPacs

FAQÂ Â

Usergroups

RSS Feed - WebSphere MQ Support

RSS Feed - Message Broker Support

MQSeries.net Forum Index » General IBM MQ Support » Duplicate message?

Duplicate message?

« View previous topic :: View next topic »

Author

Message

sac063

Posted: Thu Mar 16, 2006 5:25 am Post subject: Duplicate message?

Apprentice

Joined: 23 Jan 2004
Posts: 36

Hi All,

I am currently handling a normal EAI setup where about 40 different kind of applications talk to the broker [BizTalk 2004]. The underlying transport layer is MQ.

If the production QMGR fails or the production site fails then the BCP QMGR comes up and the remaining messages are processed. All messages are persistent.

My question is about failback.

On failback the old production QMGR is brought up and it starts processing messages as normal... since the queue buffer [q files] retains the messages even when QMGR is restarted will this not yield unexpected results like writing old messages to log on queue buffer getting full?

Also, will there be any other issues apart from queue buffer writing old messages to log...?

Any replies are much appreciated.

Thanks.

jefflowrey

Posted: Thu Mar 16, 2006 5:39 am Post subject:

Grand Poobah

Joined: 16 Oct 2002
Posts: 19981

What have you done to make the messages available to the BCP qmgr?
_________________
I am *not* the model of the modern major general.

sac063

Posted: Thu Mar 16, 2006 6:24 am Post subject:

Apprentice

Joined: 23 Jan 2004
Posts: 36

The distance between the sites is an issue to use mirroring products. Hence the messages on arriving in production are pushed into a database by the broker that resides in BCP site [using web service]

On failover they are pulled out by the broker and replayed using BCP QMGR.

But my major concern was will the messages be duplicated either in the log or in the queues on failback? Or any issues with log buffer...

jefflowrey

Posted: Thu Mar 16, 2006 8:19 am Post subject:

Grand Poobah

Joined: 16 Oct 2002
Posts: 19981

It really depends a lot on your application architecture and procedures.

Persistent messages on qmgr A will still be available after you bring it back up - assuming you've done things right.

Non persistent messages wlil be gone. And the new "non-persistent but not discarded at restart" messages may or may not be there (I don't remember how that works).

So in a large respect it will appear as if the queue manager paused for some period of time.
_________________
I am *not* the model of the modern major general.

HubertKleinmanns

Posted: Fri Mar 17, 2006 5:34 am Post subject:

Shaman

Joined: 24 Feb 2004
Posts: 732
Location: Germany

jefflowrey wrote:

And the new "non-persistent but not discarded at restart" messages may or may not be there (I don't remember how that works).

I guess, you mean the NPMCLASS attribute. This means - if set - a "normal" shutdown of a QMgr will preserve the messages (because the QMgr writes the messages to the log during QMgr ending). When a QMgr crashes, the messages are lost.
_________________
Regards
Hubert

Display posts from previous:

Page 1 of 1

MQSeries.net Forum Index » General IBM MQ Support » Duplicate message?

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Protected by Anti-Spam ACP