[rabbitmq-discuss] active/active HA and publishers/consumers

Thu Sep 8 14:45:01 BST 2011

On Thu, Sep 08, 2011 at 02:33:57PM +0100, Matthew Sackman wrote:
> On Thu, Sep 08, 2011 at 06:28:59AM -0700, John Lemp wrote:
> > I have read http://www.rabbitmq.com/ha.html several times but the only
> > specifics I see regarding client behavior is to use Consumer
> > Cancellation Notifications to re-consume from the queue, but can't
> > find any recommendations/example/best practices on how the client
> > should locate the new master?
> 
> The client shouldn't care. The point of a cluster is to have one logical
> broker spread over several machines. All resources are available from
> all machines. Unless you're hitting performance issues, you shouldn't
> care which node to connect to: the nodes in the cluster will correctly
> forward traffic around.

Thus, if you want to put transparent TCP proxies in front in order to
load-balance connections, or to do round-robin across the different
nodes in order to insulate clients from having to know how many nodes
there are and what they're called, etc, then that will be fine.

Hopefully, only in high-performance and/or low-latency use cases should
you be concerned about the number of hops messages are taking within the
cluster.

Matthew