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A document can be retrieved from a primary shard or from any of its replicas.

[[img-distrib-read]]
.Retrieving a single document
image::images/04-03_get.png[“Retrieving a single document”]

Below we list the sequence of steps to retrieve a document from either a
primary or replica shard, as depicted in <>:

1. The client sends a get request to Node 1.

2. The node uses the document’s _id to determine that the document
   belongs to shard 0. Copies of shard 0 exist on all three nodes.
   On this occasion, it forwards the request to Node 2.

3. Node 2 returns the document to Node 1 which returns the document
   to the client.

For read requests, the requesting node will choose a different shard copy on
every request in order to balance the load — it round-robins through all
shard copies.

It is possible that a document has been indexed on the primary shard but
has not yet been copied to the replica shards. In this case a replica
might report that the document doesn’t exist, while the primary would have
returned the document successfully.