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Setting up Broker instances in different machines

1. Make an exact copy of that folder in three separate machines. Let's assume MB1 is in the machine with IP1, MB2 in the machine with IP2 and MB3 in the machine with IP3.
2. Start all the above instances by running one of the following commands:
   
   • <MB_HOME>/bin/wso2server.sh (on Linux) 
   • <MB_HOME>/bin/wso2server.bat (on Windows) 
   All severs will start with port offset 0, which is 5672.

Running the broker instances

1. Start the Integrator runtime in WSO2 EI in the default port (port offset 0). This is possible if you used the single machine setup above, as those servers were started with different port offsets. If you are using different machines, use another machine to start the Integrator runtime. Instructions can be found here.

   Info
   It is not possible to start multiple WSO2 products with their default configurations simultaneously in the same environment. Since all WSO2 products use the same port in their default configuration, there will be port conflicts.

2. There is only a single difference to enable failover across the three brokers we have setup. That is when specifying the following:

   Code Block
   connectionfactory.ConnectionFactory connectionfactory.QueueConnectionFactory connectionfactory.TopicConnectionFactory

   For example, if you hope to use a single machine broker setup as described above,

   Code Block
   connectionfactory.QueueConnectionFactory = amqp://admin:admin@clientID/carbon?failover='roundrobin'&cyclecount='2'&brokerlist='tcp://localhost:5673? retries='5'&connectdelay='50';tcp://localhost:5674?retries='5'&connectdelay='50';tcp://localhost:5675?retries='5'&connectdelay='50''

   If you hope to use the broker setup made across several machines as described above,

   Code Block
   connectionfactory.QueueConnectionFactory = amqp://admin:admin@clientID/carbon?failover='roundrobin'&cyclecount='2'&brokerlist='tcp://IP1:5672?retries='5'&connectdelay='50';tcp://IP2:5672?retries='5'&connectdelay='50';tcp://IP3:5672?retries='5'&connectdelay='50''

    The parameters used above are described in detail below:

   Brokerlist option

   Code Block
   brokerlist='<broker url>[;<broker url>]'

   The broker list defines the various brokers that can be used for this connection. A minimum of one broker URL is required. Additional URLs are semi-colon(';') delimited.

   Broker URL format

   
   

   Code Block
   <transport>://<host>[:<port>][?<option>='<value>'[&<option>='<value>']]

   Option	Default	Description
   retries	1	The number of times to retry connecting to this Broker
   ssl	false	Use ssl on the connection
   connecttimeout	30000	How long in (milliseconds) to wait for the connection to succeed
   connectdelay	none	How long in (milliseconds) to wait before attempting to reconnect

   Brokerlist failover option

   
   

   Code Block
   failover='<method>[?<options>]'

   Method	Description
   singlebroker	This will only use the first broker in the list.
   roundrobin	This method tries each broker in turn.
   nofailover	[New in 0.5] This method disables all retry and failover logic.
   onetime	This option controls how failover occurs when you have a list of brokers. The value used with the failover option should contain the failover method as well as any other optional values. See the topic below on Using the failover option for details.method ensures that XA transactions do not failover from one node another. That is, if the connection fails before all transactions are committed to the broker node, all the transactions will be canceled. The client will then reconnect to the next available broker in the list and resend all the messages from the beginning. See Handling Distributed Transactions for more information

   
   The current default is to use the singlebroker method when only one broker is present, and the roundrobin method with multiple brokers. The method value in the URL may also be any valid class on the classpath that implements the FailoverMethod interface.

   Options

   Option	Default	Description
   cyclecount	1	The number of times to loop through the list of available brokers before failure.

Testing the setup