Removing resources that are on nodes that are down should happen automatically. I will take a look at that. As far as getting a list of resources that are valid that is not possible to do automatically. What a valid resource is is very much application dependent. The best way to keep the cache clean is to call delete resource on the cache when you find out that a resource is no longer up according to your applications definition of up. In this way you build a layer ontop of resource discovery that your application can rely on to present a clean cache. Make sense?