[rabbitmq-discuss] RabbitMQ clustering

Tue Nov 30 15:15:55 GMT 2010

On Mon, Nov 29, 2010 at 07:18, Kshitiz Garg <stephanion2002 at gmail.com> wrote:
> Now, if we add 4 RabbitMQ nodes in a cluster, all the credentials, exchanges
> and bindings get copied to each mnesia db. However, since the queues are
> specific to nodes, the message directed to a particular queue will be lost
> (if the node on which that queue was created is down). This seems to be a
> weak link for a scalable and High availability solution we need. Will the
> message be persisted somewhere and delivered to that queue after that
> particular node comes up?
>
> If the message is gonna lost, can we have a workaround that we create copies
> of the queues explicitly on each node. Now since they are copies, the
> exchange will send the message to all the nodes and even if a node is down,
> message will be delivered to all the copies of that queue.

In that case you will lose all the scalability you gained by setting
up a cluster,
the throughput of the whole cluster will be equal to the throughput of the
slowest node. So it's not much different than Active-Passive HA.

If you really need Active-Active HA, you have to wait. We're currently
working on it, but the development can take  a while.

Cheers,
  Marek