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melki avatar image
melki asked ·

How many replicas are required for a write with consistency QUORUM and replication factor of 3?

Suppose there is one datacenter with 5 nodes and RF=3. If I set the write consistency level to QUORUM before inserting what will be the number of expected replica nodes to satisfy.

Usually LOCAL_QUORUM takes ((RF/2)+1) no of nodes from a datacenter where the coordinator node is. I want to know if using QUORUM will suffice.

replication
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

With a replication factor of 3, write requests with a consistency of QUORUM requires a minimum of 2 replicas to acknowledge the write for the request to be considered as successful.

In your case where there is only one data centre, local quorum and quorum are equivalent since there are no remote DCs. Cheers!

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