Trouble with hazelcast deployement, can't enable clustering

I’ve problem like described below:

  • two servers (connected via external and local network

  • openfire 3.10.1 (3.10.0 behaves the same)

  • hazelcast 2.0.0

  • java jdk 1.8 (latest available)

  • firewall is off for now

What I’m doing to start it up:

Now, when I enable clustering on only one, I see in debug log it can’t connect to second one, so I’m enabling clustering on both. Both servers connect to each other, one is elected as master. From now one server are just exchanging information about who is master (log - ). Clustering stays disabled on ‘Clustering’ page, if I choose enable again and save it browser is waiting indefinitely for openfire response. None of servers is showing on ‘Cluster Overview’.

Did anyone encountered such behaviour?