Shared flowchart

Software · L4 · Quorum Write/Read and Leader Fencing

Sign in to clone

How a quorum write and read guarantee overlap, and how a fencing token protects against a stale leader acting after failover.

by @openstemUpdated Software
Client issues writeCoordinator sends to N replicasW acks received?Write acknowledged to clientWrite fails or retriesLater: client issues readCoordinator queries R replicasR overlaps W since W+R greater than NAt least one replica in R has the latest writeReturn highest-version value among R responsesOld leader stalls: GC pauseCluster times out, elects new leader with epoch+1Old leader wakes, tries to write with stale epochEpoch matches current?Write rejected: fencing token too oldWrite acceptedYesNo, timeoutNo: staleYes

We use privacy-friendly product analytics (no session recording, PII masked) to improve OpenStem. Load analytics? Privacy Policy