How does Qdrant handle sharding and replication?

Qdrant supports user-controlled sharding where a collection is split into shards distributed across cluster nodes, with each shard replicated for fault tolerance. The shard count is set at collection creation and determines write parallelism and horizontal scale. Replicas provide read scaling and high availability, with configurable consistency levels for writes. Qdrant uses Raft for cluster membership and metadata consensus, while vector data replicates between shard copies directly. Resharding is supported but requires a data movement operation.