1. A method comprising: receiving, at an indexer, a set of search affinity identifiers, each search affinity identifier indicating, for each of a plurality of sites from which a query may originate, whether the indexer has primary responsibility for responding to queries from that site for a particular subset of data accessible to the indexer; receiving, from a first search head, (i) a first query to search a subset of data accessible to the indexer, and (ii) a first site identifier identifying a first site at which the first search head is located; determining, based on both the first site identifier and a particular search affinity identifier of the set of search affinity identifiers, that the indexer is to respond to the first query with a result from searching the subset of data; sending, to the first search head, the result from searching the subset of data.