On Wed, May 16, 2018 at 7:26 PM, Michael Watters <wattersm@watters.ws> wrote:

Is it possible to have multiple engines with different versions of ovirt
running in the same cluster?  I am working on a plan to upgrade our
ovirt cluster to the 4.2 release however we would like to have a
rollback plan in case there are issues with the new engine.

If this is on a production-level setup, you anyway should have a contingency plan if anything goes bad to the engine.

I recommend automated engine setup along with regular engine backup.