activemq-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From farshad <teez_ho...@hotmail.com>
Subject Re: Question about Queue destinations in network of brokers
Date Wed, 07 Oct 2009 02:22:33 GMT

Hi Joe,

Thanks again for your reply.  Do you know when 5.3 is going to be released?

-Farshad


Joe Fernandez wrote:
> 
> Hi Farshad,
> 
> You may have encountered the following problem:
> http://issues.apache.org/activemq/browse/AMQ-2135
> 
> It is a rather nasty problem where messages become stuck in one of the
> NoB's brokers. That is, a broker does not forward the messages to other
> brokers in the NoB that have valid subscriptions. 
> 
> Not until you connect a consumer to one of the brokers that houses the
> stuck messages, will the broker  dispatch  the message to the consumer. It
> has to do with subscription management. 
> 
> There is this patch that addresses the problem, but only for
> 'fully-connected' NoB topologies. 
> 
> http://issues.apache.org/activemq/secure/attachment/17800/AMQ-2135-Patch-03182009.patch
> 
> If you're using a ring or line topology, the patch won't work and may make
> matters worse. 
> 
> You may also encounter a situation where some of the brokers’ transport
> threads are parked (stuck) on a Java CountDownLatch object and are thus
> unable to service their respective transport. A transport in this case is
> used to connect two brokers and the message broker assigns a worker thread
> to service that transport. When this occurs, the NoB is compromised. Here
> are some relevant links for this problem. 
> 
> http://www.nabble.com/Network-connector-failover-problems-td10224971.html#a10275742
> http://issues.apache.org/activemq/browse/AMQ-1827
> 
> Our testing indicated that the above 'parked thread' problem only occurs
> with the failover connector. We were never able to reproduce it with the
> static connector. 
> 
> I would also recommend moving to 5.3 when possible. 
> 
> Joe
> http://www.ttmsolutions.com
> 
> 
> farshad wrote:
>> 
>> Hi Joe,
>> 
>> Thank you for your reply.  So, I set dynamicOnly to "true" and networkTTL
>> to 4.  The sender code puts messages in the queue and the receiver code
>> connects and sometimes it gets all the messages and somtimes it gets some
>> of them.  I have to reconnect to get the rest of them.  Also, if I shut
>> down the broker that the messages were sent thru, no messages can be
>> received.  In my activemq.xml I have one broker definition and then copy
>> the same config file into the all broker machines.  Should each broker
>> have its own unique broker definition?  What is the use of
>> staticallyIncludedQuues?
>> 
>> Here's my config file:
>> 
>>  <destinations>
>>            <queue physicalName="Document.QUEUE" />
>>  </destinations>
>> 
>> <networkConnector name="myHosts"
>> uri="static://(tcp://host1:61616,tcp://host2:61616,tcp://host3:61616,tcp://host4:61616)">
>>              networkTTL=4
>>              dynamicOnly=true
>> </networkConnector>
>> 
>> <transportConnectors>
>>       <transportConnector name="openwire" uri="tcp://localhost:61616"
>> discoveryUri="multicast://default"/>
>> </transportConnectors>
>> 
>> Thank you,
>> FarshadK
>> 
>> 
>> Joe Fernandez wrote:
>>> 
>>> You should use the static and not failover connector to configure your
>>> network of brokers. Also make sure that you have the appropriate values
>>> assigned to the networkTTL and dynamicOnly parameters.  
>>> 
>>> http://activemq.apache.org/networks-of-brokers.html
>>> 
>>> Joe
>>> http://www.ttmsolutions.com
>>> 
>>> 
>>> 
>>> farshad wrote:
>>>> 
>>>> I have a network of 4 brokers configuration with
>>>> failover://(tcp://host1:61616,tcp://host2:61616,...) defined.  My first
>>>> piece of java code connects to one of these hosts (randomly) and puts
>>>> some messages in a queue destination (e.g. Document.QUEUE).  A second
>>>> piece of java code connects to another one of these hosts and fails to
>>>> read the messages.  Is this expected behaviour?  If I connect to one
>>>> host and put messages in a queue and the host goes down what do I have
>>>> to do to receive my messages connecting to another host in the network?
>>>> 
>>>> Thank you in advance,
>>>> FarshadK
>>>> 
>>> 
>>> 
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/Question-about-Queue-destinations-in-network-of-brokers-tp25776018p25779532.html
Sent from the ActiveMQ - User mailing list archive at Nabble.com.


Mime
View raw message