Glossary

Split Brain

When a network partition leaves two sides each thinking they're the leader, accepting conflicting writes.

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Definition

When a network partition leaves two sides each thinking they're the leader, accepting conflicting writes.

How it works

The classic distributed-systems failure: both halves act as primary and the data diverges. Prevented by requiring a majority quorum to act (a minority can't elect a leader) and by fencing tokens that let storage reject the stale leader's writes.

Common questions

What is Split Brain?

When a network partition leaves two sides each thinking they're the leader, accepting conflicting writes.

How does Split Brain work?

The classic distributed-systems failure: both halves act as primary and the data diverges. Prevented by requiring a majority quorum to act (a minority can't elect a leader) and by fencing tokens that let storage reject the stale leader's writes.

What is Split Brain used for in system design?

The classic distributed-systems failure: both halves act as primary and the data diverges. Prevented by requiring a majority quorum to act (a minority can't elect a leader) and by fencing tokens that let storage reject the stale leader's writes.

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