Scaling Reads medium
Your Primary database crashes. An automated system promotes a Replica to be the new Primary. What is the risk if Replication was Asynchronous?
- A Data Loss: Any writes confirmed on the old Primary but not yet copied to the Replica are lost.
- B The new Primary will be read-only.
- C The database password changes.
- D Clients cannot connect.
Answer: A. Data Loss: Any writes confirmed on the old Primary but not yet copied to the Replica are lost.
This is the trade-off of Async replication. It's fast, but durability is not guaranteed during a failover event.
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