Definition
Keeping copies of the same data on multiple nodes for availability and read scaling.
How it works
Single-leader (one node takes writes, replicas follow) is simplest and the SQL default. Multi-leader and leaderless (Dynamo/Cassandra) accept writes anywhere for availability but must resolve conflicts. Replication gives redundancy + read throughput; it does not, by itself, let you store more than one node holds — that's sharding.
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Common questions
What is Replication?
Keeping copies of the same data on multiple nodes for availability and read scaling.
How does Replication work?
Single-leader (one node takes writes, replicas follow) is simplest and the SQL default. Multi-leader and leaderless (Dynamo/Cassandra) accept writes anywhere for availability but must resolve conflicts. Replication gives redundancy + read throughput; it does not, by itself, let…
What is Replication used for in system design?
Single-leader (one node takes writes, replicas follow) is simplest and the SQL default. Multi-leader and leaderless (Dynamo/Cassandra) accept writes anywhere for availability but must resolve conflicts. Replication gives redundancy + read throughput; it does not, by itself, let…