Also see Introduction to Multi-Node Installations#NodeInstallations-LargeMulti-NodeSetups.
Each Locator Search Server acts as a node in a SolrCloud index. The index is split into shards. A shard is a logical partition of the index, containing a subset of documents, such that every document is contained in exactly one shard. The shards are automatically distributed between the Locator Search servers in the SolrCloud setup.
Deciding on number of Locator Search Servers
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