Up to now WATO assumed that one host can be assigned at most to one cluster. Now you can have one node in multiple clusters. With the new WATO ruleset Explicit mapping of Clustered Services you can now specify explicitely, to which of the clusters services of a node should be mapped.
If you are used to use main.mk then you might know clustered_services_of['myhost'], which does exactly the same, but is not accessible via WATO.
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