What is a Split-Brain scenario?

Updated Apr 28, 2026

Short answer

A failure where a cluster of nodes divides into two or more independent groups, each thinking they are the leader.

Deep explanation

Intermediate reliability engineering involves handling distributed failures and defining metrics. A failure where a cluster of nodes divides into two or more independent groups, each thinking they are the leader.

Real-world example

A mobile app retrying to connect to a server when the signal is weak.

Common mistakes

  • Retrying indefinitely without a cap, which can crash the server when it comes back up.

Follow-up questions

  • What are the three states of a Circuit Breaker?

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