[rabbitmq-discuss] upgrading a cluster

[Aaron Westendorf]

To date we've accepted the downtime associated with upgrading our
rabbit cluster as we perform that work infrequently. In evaluating our
planned improvements for the coming year, decreasing downtime is an
important goal.

With that in mind I reviewed the documentation for upgrades and found
that it is still recommended/required that the whole cluster be shut
down for an upgrade. That doesn't fit with our goals, so my questions
are:

* is that recommendation up to date?
* is it a requirement or recommendation?
* is there a configuration that would give us the benefit of
clustering and mirrored queues without this requirement?

Our use of Rabbit is fairly simple. We have a front-end web server to
handle client requests, queue messages to Rabbit, and run a pool of
consumers to handle the requests. We haven't yet evaluated other MQ
options as we've been mostly happy with Rabbit for the past 3 years,
but this required downtime is a sticking point.

-Aaron