On the correctness of Egalitarian Paxos

Pierre Sutra (1, 2, 3)

1 IP Paris - Institut Polytechnique de Paris
2 TSP - INF - Département Informatique
3 ACMES-SAMOVAR - Architecture, Cloud continuum, formal Models, artificial intElligence and Services in distributed computing

This paper identifies a problem in both the TLA+ specification and the implementation of the Egalitarian Paxos protocol. It is related to how replicas switch from one ballot to another when computing the dependencies of a command. The problem may lead replicas to diverge and break the linearizability of the replicated service.

Mots clés: Distributed systems; Fault tolerance; State-machine replication; Consensus

Domaines: Informatique [cs]

Pierre Sutra. On the correctness of Egalitarian Paxos. Information Processing Letters, 2020, 156, pp.105901:1-105901:6. ⟨10.1016/j.ipl.2019.105901⟩. ⟨hal-03488443⟩