[DOCS] Add 'remote clusters' requirement  link to CCR docs
@@ -17,6 +17,8 @@ Replication is pull-based. This means that replication is driven by the
follower index. This simplifies state management on the leader index and means
that {ccr} does not interfere with indexing on the leader index.
+IMPORTANT: {ccr-cap} requires {ref}/modules-remote-clusters.html[remote clusters].
+
[float]
=== Configuring replication
