What is a network partition?
A network partition is when a subset of the cluster cannot communicate with the rest. Messages are dropped, timeouts occur. This is common in production: GCP once had a 18-minute partition between zones, AWS EBS saw network blips lasting seconds. It is not a theoretical scenario — your system must handle it or lose data.
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The CAP Theorem Is Not a MenuNetwork partitions force a hard choice: refuse writes (CP) or accept and diverge (AP). Why the two-of-three myth is wrong, and what PACELC really tells us.
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