Resolution:
To configure BE 2.0 in FT we use Tangosol Coherence with default cluster multicast address is 224.3.1.1  and cluster port 31341. All BE 2.0 FT cluster instances running with that address that can reach each other over multi-cast will talk to each other.
Please NOTE that over a WAN, you must enable multicast traffic and you must be using unicast addresses that are visible on both ends such that the machines can "ping" each other by those addresses.

You only need to make sure that you enable this MCAST address and port.  This is for the hardware router/switch that you need to ask the network admin to enable.

If you do NOT want to use the default address and port you can :

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add the following tangosol wka (well know addresses) properties to the be-engine.xml file under $TIBCO_HOME/be/2.0/lib/com/tibco/deployment –
e.g.
&ltproperty>
        &ltname&gtjava.property.tangosol.coherence.clustername</name>
        &ltdefault&gtear1ce</default>
        &ltdescription&gtComma-separated list of trace roles to enable.</description>
    </property>
    
    &ltproperty>
        &ltname&gtjava.property.tangosol.coherence.clusteraddress</name>
        &ltdefault&gt224.3.1.9</default>
        &ltdescription&gtComma-separated list of trace roles to enable.</description>
    </property>

    &ltproperty>
        &ltname&gtjava.property.tangosol.coherence.clusterport</name>
        &ltdefault&gt31333</default>
        &ltdescription
    </property>
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Once you add the above properties, please recreate the ear file. While deploying the application you would see the above properties in the Administrator console in the "Advanced" tab of the bar file. Please modify these properties as per your environment.