load balancing 2 shibboleth IdP servers

[Joseph Fischetti]

>During upgrades we upgrade the passive site first, evaluate, then make
>it active.  Makes it easy to switch back to the old environment in case
>of any major showstoppers.

Same
Does anybody have a good mechanism for keeping things in sync?  Things like attribute resolvers/filters and metadata providers?
I find myself testing in test, verifying, and then updating each of our prod servers and reloading their services one by one.  It's cumbersome and error prone.