availability
Availability in system design interviews
Availability in system design interviews. What a nine hides, planned versus unplanned work, independent redundancy, and the user-visible error budget.
All categories
Consensus and coordination
How distributed nodes agree, elect a leader, lock a resource and finish a write that touches more than one store.
- consistency
Consensus in system design interviews
Consensus in system design interviews. Agreement, validity, and termination in plain words, why a majority works, and where it sits in a drawing.
- concurrency
Distributed locks for system design interviews
Distributed locks for system design interviews. Fencing tokens, expiry, the cases Redis misses, and the work that must not run twice.
- consistency
Distributed transactions for interviews
Distributed transactions for interviews. Why one BEGIN is gone, how outbox, saga, and 2PC differ, and a charge that must match a ledger row.
- availability
Fault tolerance for system design interviews
Fault tolerance for system design interviews. Name the fault first, then retries, isolation, bulkheads, and a store or queue that can lose a node.
- consistency
Leader election for system design interviews
Leader election for system design interviews. Why one writer exists, how leases and fencing stop a dead leader, and how to draw split brain.
- consistency
Raft consensus for system design interviews
Raft consensus for system design interviews. Leader, log, and majority, an election after a crash, and what Raft still does not give you.
- consistency
Two phase commit for system design interviews
Two phase commit for system design interviews. Prepare and commit, why the coordinator cannot vanish, and when a saga is the better story.