It is a requirement, because on reconnect due to a network partition of two non unique network connectors, if the target broker has not noticed the disconnect, it was possible to get duplicate network connectors created and potential for deadlock. Having them explicitly named allows reliable duplicate detection. This was introduced in: https://issues.apache.org/jira/browse/AMQ-3176
To have them unique, if possible give the network connector a name that reflects its usage, like wise for the broker. In your case, where there are multiple instances of the same/identical application deployed, you may want to use a system property that can be unique per app jvm and reference that in the xml configuration via org.springframework.beans.factory.config.PropertyPlaceholderConfigurer If is important that the clientId, the combination of brokerName and networkConnector name, is consistent across restarts. On 20 May 2012 21:45, Geoffrey Arnold <geoffrey.arn...@gmail.com> wrote: > Hello again, > > We are from AMQ 5.4.0 to 5.6.0, and there appears to be a new uniqueness > constraint in network connector names in network-of-brokers configurations. > > Here's our setup: > - N copies of a producer application; each copy of the producer application > consists of an embedded broker with 2 network connectors pointing at an > embedded broker in the consumer application > - 1 consumer application; the consumer application consists of an embedded > broker with 2 transport connectors > > Messages in the consumer application are sent to the embedded broker, which > pushes those messages to the embedded broker in the consumer application over > the network/transport connectors, and are consumed by listeners on the > embedded broker in the consumer application. > > In AMQ 5.4.0, the name of the network connectors in the embedded broker in > the producer application were not required to be unique across copies of the > application, ie. for each copy of the producer application used the same name > for each network connector. In AMQ 5.6.0, we receive the following error > when starting a second copy of the producer application: > > > In the producer application: > > Network connection between vm://producerBroker#4 and > tcp://localhost/127.0.0.1:61616 shutdown due to a remote error: > javax.jms.InvalidClientIDException: Broker: consumerBroker - Client: > networkConnector1_producerBroker_outbound already connected from > tcp://127.0.0.1:62961 > > > In the consumer application: > > Async error occurred: javax.jms.InvalidClientIDException: Broker: > consumerBroker - Client: networkConnector1_producerBroker_outbound already > connected from tcp://127.0.0.1:62963 > javax.jms.InvalidClientIDException: Broker: consumerBroker - Client: > networkConnector1_producerBroker_outbound already connected from > tcp://127.0.0.1:62963 > at > org.apache.activemq.broker.region.RegionBroker.addConnection(RegionBroker.java:223) > at > org.apache.activemq.broker.BrokerFilter.addConnection(BrokerFilter.java:85) > at > org.apache.activemq.advisory.AdvisoryBroker.addConnection(AdvisoryBroker.java:65) > at > org.apache.activemq.broker.BrokerFilter.addConnection(BrokerFilter.java:85) > at > org.apache.activemq.broker.BrokerFilter.addConnection(BrokerFilter.java:85) > at > org.apache.activemq.broker.BrokerFilter.addConnection(BrokerFilter.java:85) > at > org.apache.activemq.security.SimpleAuthenticationBroker.addConnection(SimpleAuthenticationBroker.java:97) > at > org.apache.activemq.broker.MutableBrokerFilter.addConnection(MutableBrokerFilter.java:91) > at > org.apache.activemq.broker.TransportConnection.processAddConnection(TransportConnection.java:715) > at > org.apache.activemq.broker.jmx.ManagedTransportConnection.processAddConnection(ManagedTransportConnection.java:79) > at > org.apache.activemq.command.ConnectionInfo.visit(ConnectionInfo.java:139) > at > org.apache.activemq.broker.TransportConnection.service(TransportConnection.java:292) > at > org.apache.activemq.broker.TransportConnection$1.onCommand(TransportConnection.java:150) > at > org.apache.activemq.transport.MutexTransport.onCommand(MutexTransport.java:50) > at > org.apache.activemq.transport.WireFormatNegotiator.onCommand(WireFormatNegotiator.java:113) > at > org.apache.activemq.transport.AbstractInactivityMonitor.onCommand(AbstractInactivityMonitor.java:229) > at > org.apache.activemq.transport.TransportSupport.doConsume(TransportSupport.java:83) > at > org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:222) > at > org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:204) > at java.lang.Thread.run(Thread.java:680) > > > Is this a regression or a new requirement. If it's a new requirement, what > strategy would you recommend to ensure uniqueness in network connector names? > > Thanks in advance, > Geoff. -- http://fusesource.com http://blog.garytully.com
