The Event Monitor scope identifies the portions of an AD environment that are relevant for event monitoring purposes. Setting the scope allows File Dynamics to generate actionable events only for the appropriate containers and groups. A scope is defined by explicit Include and/or Exclude lists. You can define a scope to encompass a multi-domain forest environment with subsets of scoped elements being individual AD domains and containers or group objects within them.
The Event Monitor scope does not affect the AD Forest Trust Filter or Storage Resources. These have separate configuration mechanisms that limit what portions of the AD environment they make use of. However, an AD Forest Trust Filter can affect the scope if the filter excludes entire AD forests that are otherwise included by the scope. The accessible portions of AD will be the intersection of the AD Forest Trust Filter and the scope. Or, to put it another way, every AD forest that is included by the AD Forest Trust Filter will, by default, have all of its AD domains also implicitly included in the absence of a scope that explicitly excludes any AD domains.