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| <appendix xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="Java-Broker-Appendix-Queue-Alerts"> |
| <title>Queue Alerts</title> |
| <para>The Broker supports a variety of queue alerting thresholds. Once configured on a queue, |
| these limits will be periodically written to the log if these limits are breached, until the |
| condition is rectified.</para> |
| <para>For example, if queue <literal>myqueue</literal> is configured with a message count alert of |
| 1000, and then owing to a failure of a downstream system messages begin to accumulate on the |
| queue, the following alerts will be written periodically to the log. </para> |
| <screen>INFO [default:VirtualHostHouseKeepingTask] (queue.NotificationCheck) - MESSAGE_COUNT_ALERT On Queue myqueue - 1272: Maximum count on queue threshold (1000) breached. |
| </screen> |
| <para>Note that queue alerts are <emphasis>soft</emphasis> in nature; breaching the limit will |
| merely cause the alerts to be generated but messages will still be accepted to the queue.</para> |
| <table pgwide="1" xml:id="Java-Broker-Appendix-Queue-Alerts-Alerting-Messages"> |
| <title>Queue Alerts</title> |
| <tgroup cols="2"> |
| <colspec colnum="1" colname="alertname" colwidth="1*"/> |
| <colspec colnum="2" colname="purpose" colwidth="1*"/> |
| <thead> |
| <row> |
| <entry>Alert Name</entry> |
| <entry>Alert Format and Purpose</entry> |
| </row> |
| </thead> |
| <tbody> |
| <row> |
| <entry morerows="1">MESSAGE_COUNT_ALERT</entry> |
| <entry> MESSAGE_COUNT_ALERT On Queue <replaceable>queuename</replaceable> - |
| <replaceable>number of messages</replaceable>: Maximum count on queue threshold |
| (<replaceable>limit</replaceable>) breached. </entry> |
| </row> |
| <row> |
| <entry> |
| <para>The number of messages on the given queue has breached its configured |
| limit.</para> |
| </entry> |
| </row> |
| <row> |
| <entry morerows="1">MESSAGE_SIZE_ALERT</entry> |
| <entry> MESSAGE_SIZE_ALERT On Queue <replaceable>queuename</replaceable> |
| -<replaceable>message size</replaceable> : Maximum message size threshold |
| (<replaceable>limit</replaceable>) breached. [Message ID=<replaceable>message |
| id</replaceable>]</entry> |
| </row> |
| <row> |
| <entry> |
| <para>The size of an individual messages has breached its configured limit.</para> |
| </entry> |
| </row> |
| <row> |
| <entry morerows="1">QUEUE_DEPTH_ALERT</entry> |
| <entry> QUEUE_DEPTH_ALERT On Queue <replaceable>queuename</replaceable> - |
| <replaceable>total size of all messages on queue</replaceable> : Maximum queue depth |
| threshold (<replaceable>limit</replaceable>) breached.</entry> |
| </row> |
| <row> |
| <entry> |
| <para>The total size of all messages on the queue has breached its configured |
| limit.</para> |
| </entry> |
| </row> |
| <row> |
| <entry morerows="1">MESSAGE_AGE_ALERT</entry> |
| <entry>MESSAGE_AGE_ALERT On Queue <replaceable>queuename</replaceable> - <replaceable>age |
| of message</replaceable> : Maximum age on queue threshold |
| (<replaceable>limit</replaceable>) breached. </entry> |
| </row> |
| <row> |
| <entry> |
| <para>The age of a message on the given queue has breached its configured limit.</para> |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </table> |
| </appendix> |