Bug 677358

Summary: Durable Queue vs Persistent Message ?
Product: Red Hat Enterprise MRG Reporter: Raymond Mancy <rmancy>
Component: Messaging_Programming_ReferenceAssignee: Joshua Wulf <jwulf>
Status: CLOSED NEXTRELEASE QA Contact: ecs-bugs
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 1.3CC: ebaak, jwulf, lcarlon
Target Milestone: 2.2   
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Hardware: Unspecified   
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Fixed In Version: Doc Type: Bug Fix
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Last Closed: 2012-04-25 14:23:20 UTC Type: ---
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Description Raymond Mancy 2011-02-14 13:45:11 UTC 
Hi,
In the "Messaging User Guide" in section 6.1. Persistent Messages, Durable Queues, and Guaranteed Delivery it has the following:

"In MRG Messaging, message persistence is used for persistent messages that are placed on durable queues. A durable queue is a queue that is associated with a persistent store. A queue must be declared persistent at the time it is created. For instance, in C++, the following code creates a durable queue:

session.queueDeclare(arg::queue=name, arg::durable=true);"

The part I find confusing is.

"A durable queue..."
"A queue must be declared persistent..."
"the following code creates a durable queue..."

I'm not sure if durable is being uses synonymously with persistent ?
Is a queue declared persistent by passing the durable arg?

Thanks
Comment 1 Joshua Wulf 2012-04-25 14:23:20 UTC 
This book is being rewritten for 2.2, so I'm closing this bug, after noting the confusion caused by the wording of the existing book.

This quick explanation might make the situation clearer:

Durable queues can save persistent messages across server restarts, to redeliver them when the server starts again.

For the message to survive a shutdown of the server, it must be (a) marked persistent and (b) sent to a durable queue.

A queue is marked as durable by creating it with the durable argument.