What is the best practice for managing multiple clusters from one manager? Do all database changes show up across all policies even if they aren't referenced in the policy? Thank you.
If you are referring to the objects managed by SMS and not MDM, then yes, those will be common to all policies. So long as you are using a Security Management Server, you are operating in a single Security Domain.
So long as the clusters in question are under purview of the same organization they could be administered by common policy and using shared objects.
Multi Domain Manager (or Multi Domain Server), as the name implies, managing segregated databases with the ability have a Global Policy with common Global Objects.
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