谁是rabbitmq 集群管理员？ 如何从集群中获取数据？

Question

I created rabbitmq cluster. There are three nodes one master two slaves. When master dies, who decides which slave is the new master. Who is cluster manager? And How can I get data from cluster. I can get message from every node from cluster but For example: I am getting data from master node, but when master node is dead, I need to connect to other node manually. But I want to connect to cluster and Whenever master dies, I could get message from another node?

Answer 1

If the queue master node stops, your application will receive a "connection lost" exception. You then act upon this exception to connect to any other node in the cluster.

You don't need to know anything about a "cluster manager". Just connect to another node.

The RabbitMQ Java client library supports automatic recovery for connections and topologies.

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Answer 2

There's not sth like "cluster manager" . The nodes in a RabbitMQ cluster use the Raft algorithm for distributed consensus and elect their leader (see http://thesecretlivesofdata.com/raft ).

On the other hand, RabbitMQ Java Client API already could manage disconnections as in the scenario that you pose. New connections are recoverable by default (see https://www.rabbitmq.com/api-guide.html#connection-recovery ).

You could use this snippet as an example to create connections to several nodes (each String in the addressesStr List should be like node_ip:port ):

  public Connection crateConnection(final List<String> addressesStr)
      throws IOException, TimeoutException {
    final ConnectionFactory factory = new ConnectionFactory();
    final List<Address> addresses = new ArrayList<>();

    for (final String address : addressesStr) {
      final String[] addr = address.split(":");
      final String host = addr[0];
      final var port = Integer.parseInt(addr[1]);
      addresses.add(new Address(host, port));
    }

    return factory.newConnection(addresses);
  }