I'm guessing here because I don't really know the relevant code, but maybe when you don't set useJmx="true", it's creating two different JMX contexts for your broker? I can't explain why that would be, but maybe someone else here can.
However, another user appeared to have the same problem two years ago, but never found an explanation: http://activemq.2283324.n4.nabble.com/useJmx-false-two-brokers-getting-exception-due-to-jmx-td4671456.html Either way, it sounds like you've got the system running and don't need any more help with this. Am I right? Tim On Fri, Jul 3, 2015 at 2:48 AM, softwbc <soft...@163.com> wrote: > Thank you for your prompt > > I set the useJMX=true, the warning message disappears. > > and i dont know why... > > > > -- > View this message in context: > http://activemq.2283324.n4.nabble.com/Using-Broker-clusters-javax-management-InstanceAlreadyExistsException-xx-tp4698127p4698547.html > Sent from the ActiveMQ - User mailing list archive at Nabble.com. >
