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svn commit: r1028347 - in /websites/production/activemq/content:
cache/main.pageCache virtual-destinations.html
Author: buildbot
Date: Fri Apr 13 10:23:57 2018
New Revision: 1028347
Log:
Production update by buildbot for activemq
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websites/production/activemq/content/cache/main.pageCache
websites/production/activemq/content/virtual-destinations.html
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<title>
Apache ActiveMQ ™ -- Virtual Destinations
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-<div class="wiki-content maincontent"><p><em>Virtual Destinations</em> allow us to create logical destinations that clients can use to produce and consume from but which map onto one or more <em>physical destinations</em>. It allows us to provide more flexible loosely coupled messaging configurations.</p><h2 id="VirtualDestinations-VirtualTopics">Virtual Topics</h2><p>The idea behind <em>publish subscribe</em> is a great one. Allow producers to be decoupled from consumers so that they do not even know how many consumers are interested in the messages they publish. The JMS specification defines support for durable topics however they have limitations as we will describe...</p><h3 id="VirtualDestinations-ThelimitationsofJMSdurabletopics">The limitations of JMS durable topics</h3><p>A JMS durable subscriber MessageConsumer is created with a unique JMS clientID and durable subscriber name. To be JMS compliant only one JMS connection can be active at any point in time for one JMS clientI
D, and only one consumer can be active for a clientID and subscriber name. i.e., only <strong>one</strong> thread can be actively consuming from a given logical topic subscriber. This means we cannot implement</p><ul><li>load balancing of messages.</li><li>fast failover of the subscriber if that one process running that one consumer thread dies.</li></ul><p>Now <em>queue</em> semantics in JMS offer the ability to load balance work across a number of consumers in a reliable way - allowing many threads, processes and machines to be used to process messages. Then we have sophisticated sticky load balancing techniques like <a shape="rect" href="message-groups.html">Message Groups</a> to load balance and parallelise work while maintaining ordering.</p><p>Another added benefit of having physical queues for each logical topic subscriber is we can then monitor the queue depths via <a shape="rect" href="jmx.html">JMX</a> to monitor system performance together with being able to browse these
physical queues.</p><h3 id="VirtualDestinations-VirtualTopicstotherescue">Virtual Topics to the rescue</h3><p>The idea behind virtual topics is that producers send to a topic in the usual JMS way. Consumers can continue to use the Topic semantics in the JMS specification. However if the topic is virtual, consumer can consume from a physical queue for a logical topic subscription, allowing many consumers to be running on many machines & threads to load balance the load.</p><p>E.g., let's say we have a topic called <strong>VirtualTopic.Orders</strong>. (Where the prefix VirtualTopic. indicates its a virtual topic). And we logically want to send orders to systems A and B. Now with regular durable topics we'd create a JMS consumer for clientID_A and "A" along with clientID_B and "B".</p><p>With virtual topics we can just go right ahead and consume to queue <strong>Consumer.A.VirtualTopic.Orders</strong> to be a consumer for system A or consume to <strong>Consumer.B.VirtualTopic.Orde
rs</strong> to be a consumer for system B.</p><p>We can now have a pool of consumers for each system which then compete for messages for systems A or B such that all the messages for system A are processed exactly once and similarly for system B.</p><h3 id="VirtualDestinations-Customizingtheout-of-the-boxdefaults">Customizing the out-of-the-box defaults</h3><p>The out-of-the-box defaults are described above. Namely that the only virtual topics available must be within the <strong>VirtualTopic.></strong> namespace and that the consumer queues are named <strong>Consumer.*.VirtualTopic.></strong>.</p><p>You can configure this to use whatever naming convention you wish. The following <a shape="rect" class="external-link" href="https://svn.apache.org/repos/asf/incubator/activemq/trunk/activemq-unit-tests/src/test/resources/org/apache/activemq/broker/virtual/global-virtual-topics.xml">example</a> shows how to make all topics virtual topics. The example below is using the name <stron
g>></strong> to indicate 'match all topics'. You could use this wildcard to apply different virtual topic policies in different hierarchies.</p><pre><span style="color: rgb(0,0,0);"><destinationInterceptors> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualTopic name=">" prefix="VirtualTopicConsumers.*." selectorAware="false"/> </span> </pre><pre> </virtualDestinations></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"></destinationInterceptors></span></pre><p> </p><p>Note that making a topic virtual does add a small CPU overhead when sending messages to the topic but it is fairly small.</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" c
lass="confluenceTh">Option</th><th colspan="1" rowspan="1" class="confluenceTh">Default</th><th colspan="1" rowspan="1" class="confluenceTh">Description</th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">selectorAware</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">only messages that match one of the existing subscribers are actually dispatched. Using this option prevents the build up of unmatched messages when selectors are used by exclusive consumers</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">local</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, don't fan out messages that were received over a network</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">concurrentSend</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, use an executor t
o fanout such that sends occur in parallel. This allows the journal to batch writes which will reduce disk io (5.12)</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">transactedSend</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, use a transaction for fanout sends such that there is a single disk sync. A local broker transaction will be created if there is no client transaction (5.13)</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><span>dropOnResourceLimit</span></td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, ignore any ResourceAllocationException thrown during fanout (see: sendFailIfNoSpace policy entry) (5.16)</td></tr></tbody></table></div><p> </p><h2 id="VirtualDestinations-CompositeDestinations">Composite Destinations</h2><p>Composite Destinations allow for one-to-many relationships on individual d
estinations; the main use case is for <em>composite queues</em>. For example when a message is sent to queue A you may want to forward it also to queues B and C and topic D. Composite destinations are then a mapping from a virtual destination to a collection of other physical destinations. In this case the mapping is broker side and the client is unaware of the mapping between the destinations. This is different from client side <a shape="rect" href="composite-destinations.html">Composite Destinations</a> where the client uses a URL notation to specify the actual physical destinations that a message must be sent to.</p><p>The following <a shape="rect" class="external-link" href="http://svn.apache.org/repos/asf/incubator/activemq/trunk/activemq-unit-tests/src/test/resources/org/apache/activemq/broker/virtual/composite-queue.xml">example</a> shows how to set up a <strong><compositeQueue/></strong> element in the XML configuration so that when a message is sent to <code>MY.QUEUE<
/code> then it is really forwarded to the physical queue <code>FOO</code> and the topic <code>BAR</code>.</p><pre><span style="color: rgb(0,0,0);"><destinationInterceptors></span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <compositeQueue name="MY.QUEUE"></span></pre><pre><span style="color: rgb(0,0,0);"> <forwardTo></span></pre><pre><span style="color: rgb(0,0,0);"> <queue physicalName="FOO" /> </span></pre><pre><span style="color: rgb(0,0,0);"> <topic physicalName="BAR" /></span></pre><pre><span style="color: rgb(0,0,0);"> </forwardTo></span></pre><pre><span style="color: rgb(0,0,0);"> </compositeQueue></span></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinations></span></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinationInterceptor></
span></pre><pre><span style="color: rgb(0,0,0);"></destinationInterceptors></span></pre><p> </p><p>By default, subscribers cannot consume messages directly from a composite queue or topic - it is a logical construct only. Given the configuration above, subscribers can only consume messages from <code>FOO</code> and <code>BAR</code>; but not <code>MY.QUEUE</code>.</p><p>This behaviour can be altered to implement use cases such as watching a queue by sending the same messages to a notification topic (wire tapping), by setting the optionally set <code>forwardOnly</code> attribute to false.</p><pre><compositeQueue name="IncomingOrders" forwardOnly="false"> </pre><pre> <forwardTo></pre><pre> <topic physicalName="Notifications" /></pre><pre> </forwardTo></pre><pre> </compositeQueue></pre><p> </p><p>Messages sent to <code>IncomingOrders</code> will all be copied and forwarded to <code>Notifications</code>, before being placed on the phys
ical <code>IncomingOrders</code> queue for consumption by subscribers.</p><p>Where the <code>forwardOnly</code> attribute is not defined or is set to <code>true</code>, there is no logical difference between a <code>compositeQueue</code> and a <code>compositeTopic</code> - they can be used interchangeably. It is only when a composite destination is made physical through the use of <code>forwardOnly</code> that the choice of <code>compositeTopic</code>/<code>compositeQueue</code> has an impact on behavior.</p><h3 id="VirtualDestinations-Usingfiltereddestinations">Using filtered destinations</h3><p>From Apache ActiveMQ <strong>4.2</strong> onwards you can now use selectors to define virtual destinations.</p><p>You may wish to create a virtual destination which forwards messages to multiple destinations but applying a selector first to decide if the message really does have to go to a particular destination.</p><p>The following example shows how a message sent to the virtual destinatio
n <strong>MY.QUEUE</strong> will be forwarded to <strong>FOO</strong> and <strong>BAR</strong> if the selectors match</p><pre><destinationInterceptors> <virtualDestinationInterceptor> <virtualDestinations> </pre><pre> <compositeQueue name="MY.QUEUE"></pre><pre> <forwardTo></pre><pre> <filteredDestination selector="odd = 'yes'" queue="FOO"/></pre><pre> <filteredDestination selector="i = 5" topic="BAR"/></pre><pre> </forwardTo></pre><pre> </compositeQueue></pre><pre></virtualDestinations> </virtualDestinationInterceptor> </destinationInterceptors></pre><p> </p><h2 id="VirtualDestinations-AvoidingDuplicateMessageinaNetworkofBrokers">Avoiding Duplicate Message in a Network of Brokers</h2><p><strong>TLDR</strong>: bridge consumer queues or virtual topics, not both.</p><p>Typically you would network consumer queues. In this case it is important to not bridge any normal topic consumer on the virtu
al topic because any forwarded message would again get fanned out to consumer queues on the networked broker, leading to duplicates.</p><p>It is also possible to bridge the virtual topic in which case it is necessary exclude the consumer queues from any network connector configuration. </p><p>Here is an example of how to exclude virtual topic consumer queues:</p><pre><span style="color: rgb(0,0,0);"><networkConnectors> <networkConnector uri="static://(<a shape="rect" href="tcp://localhost:61617" rel="nofollow">tcp://localhost:61617</a>)"></span></pre><pre><span style="color: rgb(0,0,0);"> <excludedDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <queue physicalName="Consumer.*.VirtualTopic.>"/> </span></pre><pre><span style="color: rgb(0,0,0);"> </excludedDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"></networkConnector> </networkConnectors></span></pre><p> </p></div>
+<div class="wiki-content maincontent"><p><em>Virtual Destinations</em> allow us to create logical destinations that clients can use to produce and consume from but which map onto one or more <em>physical destinations</em>. It allows us to provide more flexible loosely coupled messaging configurations.</p><h2 id="VirtualDestinations-VirtualTopics">Virtual Topics</h2><p>The idea behind <em>publish subscribe</em> is a great one. Allow producers to be decoupled from consumers so that they do not even know how many consumers are interested in the messages they publish. The JMS specification defines support for durable topics however they have limitations as we will describe...</p><h3 id="VirtualDestinations-ThelimitationsofJMSdurabletopics">The limitations of JMS durable topics</h3><p>A JMS durable subscriber MessageConsumer is created with a unique JMS clientID and durable subscriber name. To be JMS compliant only one JMS connection can be active at any point in time for one JMS clientI
D, and only one consumer can be active for a clientID and subscriber name. i.e., only <strong>one</strong> thread can be actively consuming from a given logical topic subscriber. This means we cannot implement</p><ul><li>load balancing of messages.</li><li>fast failover of the subscriber if that one process running that one consumer thread dies.</li></ul><p>Now <em>queue</em> semantics in JMS offer the ability to load balance work across a number of consumers in a reliable way - allowing many threads, processes and machines to be used to process messages. Then we have sophisticated sticky load balancing techniques like <a shape="rect" href="message-groups.html">Message Groups</a> to load balance and parallelise work while maintaining ordering.</p><p>Another added benefit of having physical queues for each logical topic subscriber is we can then monitor the queue depths via <a shape="rect" href="jmx.html">JMX</a> to monitor system performance together with being able to browse these
physical queues.</p><h3 id="VirtualDestinations-VirtualTopicstotherescue">Virtual Topics to the rescue</h3><p>The idea behind virtual topics is that producers send to a topic in the usual JMS way. Consumers can continue to use the Topic semantics in the JMS specification. However if the topic is virtual, consumer can consume from a physical queue for a logical topic subscription, allowing many consumers to be running on many machines & threads to load balance the load.</p><p>E.g., let's say we have a topic called <strong>VirtualTopic.Orders</strong>. (Where the prefix VirtualTopic. indicates its a virtual topic). And we logically want to send orders to systems A and B. Now with regular durable topics we'd create a JMS consumer for clientID_A and "A" along with clientID_B and "B".</p><p>With virtual topics we can just go right ahead and consume to queue <strong>Consumer.A.VirtualTopic.Orders</strong> to be a consumer for system A or consume to <strong>Consumer.B.VirtualTopic.Orde
rs</strong> to be a consumer for system B.</p><p>We can now have a pool of consumers for each system which then compete for messages for systems A or B such that all the messages for system A are processed exactly once and similarly for system B.</p><h3 id="VirtualDestinations-Customizingtheout-of-the-boxdefaults">Customizing the out-of-the-box defaults</h3><p>The out-of-the-box defaults are described above. Namely that the only virtual topics available must be within the <strong>VirtualTopic.></strong> namespace and that the consumer queues are named <strong>Consumer.*.VirtualTopic.></strong>.</p><p>You can configure this to use whatever naming convention you wish. The following <a shape="rect" class="external-link" href="https://svn.apache.org/repos/asf/incubator/activemq/trunk/activemq-unit-tests/src/test/resources/org/apache/activemq/broker/virtual/global-virtual-topics.xml">example</a> shows how to make all topics virtual topics. The example below is using the name <stron
g>></strong> to indicate 'match all topics'. You could use this wildcard to apply different virtual topic policies in different hierarchies.</p><pre><span style="color: rgb(0,0,0);"><destinationInterceptors> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualTopic name=">" prefix="VirtualTopicConsumers.*." selectorAware="false"/> </span> </pre><pre> </virtualDestinations></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"></destinationInterceptors></span></pre><p> </p><p>Note that making a topic virtual does add a small CPU overhead when sending messages to the topic but it is fairly small.</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" c
lass="confluenceTh">Option</th><th colspan="1" rowspan="1" class="confluenceTh">Default</th><th colspan="1" rowspan="1" class="confluenceTh">Description</th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">selectorAware</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">only messages that match one of the existing subscribers are actually dispatched. Using this option prevents the build up of unmatched messages when selectors are used by exclusive consumers</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">local</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, don't fan out messages that were received over a network</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">concurrentSend</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, use an executor t
o fanout such that sends occur in parallel. This allows the journal to batch writes which will reduce disk io (5.12)</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">transactedSend</td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, use a transaction for fanout sends such that there is a single disk sync. A local broker transaction will be created if there is no client transaction (5.13)</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><span>dropOnResourceLimit</span></td><td colspan="1" rowspan="1" class="confluenceTd">false</td><td colspan="1" rowspan="1" class="confluenceTd">when true, ignore any ResourceAllocationException thrown during fanout (see: sendFailIfNoSpace policy entry) (5.16)</td></tr></tbody></table></div><p> </p><h2 id="VirtualDestinations-VirtualSelectorCacheBrokerPlugin"><span style="color: rgb(0,0,0);">VirtualSelectorCacheBrokerPlugin</span></h2><p><span style="
color: rgb(0,0,0);">When selectorAware=true, only active consumers are condidered for selector matching. If consumers disconnect and reconnect they will miss messages. The intent of selectorAware=true is to not have messages build up. </span><span style="color: rgb(0,0,0);">The virtualSelectorCacheBrokerPlugin provides a cache that tracks the selectors associated with a destination by a consumers such that they can apply in the absense of that consumer. In this way the just the selected messages build up. The existing set of selectors can be persisted such that it can be recovered on restart. the plugin is applied in the normal way to the plugins section.</span></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;"><plugins>
+ <virtualSelectorCacheBrokerPlugin persistFile="<some path>/selectorcache.data" />
+</plugins></pre>
+</div></div><p>Note: the persistFile option uses java serialisation that should be locked down <span style="color: rgb(0,0,0);">with an appropriate </span><a shape="rect" class="external-link" href="http://openjdk.java.net/jeps/290" rel="nofollow">jdk.serialFilter</a> that allows ConcurrentHashMap</p><p><span style="color: rgb(106,106,106);"><span style="color: rgb(106,106,106);"> </span></span></p><h2 id="VirtualDestinations-CompositeDestinations">Composite Destinations</h2><p>Composite Destinations allow for one-to-many relationships on individual destinations; the main use case is for <em>composite queues</em>. For example when a message is sent to queue A you may want to forward it also to queues B and C and topic D. Composite destinations are then a mapping from a virtual destination to a collection of other physical destinations. In this case the mapping is broker side and the client is unaware of the mapping between the destinations. This is different from clie
nt side <a shape="rect" href="composite-destinations.html">Composite Destinations</a> where the client uses a URL notation to specify the actual physical destinations that a message must be sent to.</p><p>The following <a shape="rect" class="external-link" href="http://svn.apache.org/repos/asf/incubator/activemq/trunk/activemq-unit-tests/src/test/resources/org/apache/activemq/broker/virtual/composite-queue.xml">example</a> shows how to set up a <strong><compositeQueue/></strong> element in the XML configuration so that when a message is sent to <code>MY.QUEUE</code> then it is really forwarded to the physical queue <code>FOO</code> and the topic <code>BAR</code>.</p><pre><span style="color: rgb(0,0,0);"><destinationInterceptors></span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinationInterceptor> </span></pre><pre><span style="color: rgb(0,0,0);"> <virtualDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <compositeQueue name="
MY.QUEUE"></span></pre><pre><span style="color: rgb(0,0,0);"> <forwardTo></span></pre><pre><span style="color: rgb(0,0,0);"> <queue physicalName="FOO" /> </span></pre><pre><span style="color: rgb(0,0,0);"> <topic physicalName="BAR" /></span></pre><pre><span style="color: rgb(0,0,0);"> </forwardTo></span></pre><pre><span style="color: rgb(0,0,0);"> </compositeQueue></span></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinations></span></pre><pre><span style="color: rgb(0,0,0);"> </virtualDestinationInterceptor></span></pre><pre><span style="color: rgb(0,0,0);"></destinationInterceptors></span></pre><p> </p><p>By default, subscribers cannot consume messages directly from a composite queue or topic - it is a logical construct only. Given the configuration above, subscribers can only consume messages from <code>FOO</code> and <code>BAR</code>; but not <code>MY.QUEUE</code>.</p><p>This behaviour can be altered to implement
use cases such as watching a queue by sending the same messages to a notification topic (wire tapping), by setting the optionally set <code>forwardOnly</code> attribute to false.</p><pre><compositeQueue name="IncomingOrders" forwardOnly="false"> </pre><pre> <forwardTo></pre><pre> <topic physicalName="Notifications" /></pre><pre> </forwardTo></pre><pre> </compositeQueue></pre><p> </p><p>Messages sent to <code>IncomingOrders</code> will all be copied and forwarded to <code>Notifications</code>, before being placed on the physical <code>IncomingOrders</code> queue for consumption by subscribers.</p><p>Where the <code>forwardOnly</code> attribute is not defined or is set to <code>true</code>, there is no logical difference between a <code>compositeQueue</code> and a <code>compositeTopic</code> - they can be used interchangeably. It is only when a composite destination is made physical through the use of <code>forwardOnly</code> that the choice
of <code>compositeTopic</code>/<code>compositeQueue</code> has an impact on behavior.</p><h3 id="VirtualDestinations-Usingfiltereddestinations">Using filtered destinations</h3><p>From Apache ActiveMQ <strong>4.2</strong> onwards you can now use selectors to define virtual destinations.</p><p>You may wish to create a virtual destination which forwards messages to multiple destinations but applying a selector first to decide if the message really does have to go to a particular destination.</p><p>The following example shows how a message sent to the virtual destination <strong>MY.QUEUE</strong> will be forwarded to <strong>FOO</strong> and <strong>BAR</strong> if the selectors match</p><pre><destinationInterceptors> <virtualDestinationInterceptor> <virtualDestinations> </pre><pre> <compositeQueue name="MY.QUEUE"></pre><pre> <forwardTo></pre><pre> <filteredDestination selector="odd = 'yes'" queue="FOO"/></pre><pre> <filteredDestinatio
n selector="i = 5" topic="BAR"/></pre><pre> </forwardTo></pre><pre> </compositeQueue></pre><pre></virtualDestinations> </virtualDestinationInterceptor> </destinationInterceptors></pre><p> </p><h2 id="VirtualDestinations-AvoidingDuplicateMessageinaNetworkofBrokers">Avoiding Duplicate Message in a Network of Brokers</h2><p><strong>TLDR</strong>: bridge consumer queues or virtual topics, not both.</p><p>Typically you would network consumer queues. In this case it is important to not bridge any normal topic consumer on the virtual topic because any forwarded message would again get fanned out to consumer queues on the networked broker, leading to duplicates.</p><p>It is also possible to bridge the virtual topic in which case it is necessary exclude the consumer queues from any network connector configuration. </p><p>Here is an example of how to exclude virtual topic consumer queues:</p><pre><span style="color: rgb(0,0,0);"><networkConnec
tors> <networkConnector uri="static://(<a shape="rect" href="tcp://localhost:61617" rel="nofollow">tcp://localhost:61617</a>)"></span></pre><pre><span style="color: rgb(0,0,0);"> <excludedDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"> <queue physicalName="Consumer.*.VirtualTopic.>"/> </span></pre><pre><span style="color: rgb(0,0,0);"> </excludedDestinations> </span></pre><pre><span style="color: rgb(0,0,0);"></networkConnector> </networkConnectors></span></pre><p> </p></div>
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