PPT-Paxos A Consensus Algorithm for

Fault Tolerant Replication CS 5204 Fall 2008 System Model Messages possible indefinite delay possible duplication or loss delivered messages not corrupted replicas client Replicas. lastclcamacuk ABSTRACT The Paxos algorithm is famously dif64257cult to reason about and even more so to implement despite having been synonymous with dis tributed consensus for over a decade The recently proposed Raft protocol lays claim to being a n Ali Ghodsi. alig@cs.berkeley.edu. Replicated State Machine (RSM). Distributed Systems 101. Fault-tolerance. . (partial, byzantine, recovery,...). Concurrency. (ordering, asynchrony, timing,...). Generic. A Consensus Algorithm for . Fault Tolerant Replication. CS 5204 – Fall, 2008. System Model. Messages. possible indefinite delay. possible duplication or loss. delivered messages not corrupted. . . .. Advanced Topics in Computer Systems. Lecture 24. Paxos/Megastore. November . 26. th. , . 2012. John . Kubiatowicz. and Anthony D. Joseph. Electrical Engineering and Computer Sciences. University of California, Berkeley. Paxos. --- 1. Steve Ko. Computer Sciences and Engineering. University at Buffalo. Recap. NFS. Caching with write-through policy at close(). Stateless server. One power efficient design: FAWN. Embedded CPUs & Flash . Burcu Canakci & Matt Burke. . Outline. Consensus. The Part-Time Parliament. Single-Decree Paxos. Liveness. Multi-Decree Paxos. Paxos Variants. Conclusion. Outline. Consensus. The Part-Time Parliament. Distributed Systems. Lecture 12. Michael Freedman. Let different replicas assume role of primary over time. System moves through a sequence of views. How do the nodes agree on view / primary?. 2. Recall the use of Views. . Distributed. . Systems. Crash. . Fault. . Tolerance. Sisi. . Duan. Assistant. . Professor. Information. . Systems. sduan@umbc.edu. Outline. A. . brief. . history. . of. . consensus. Paxos. Ethan Cecchetti. October 18, 2016. CS6410. . Some structure taken from Robert Burgess’s 2009 slides on this topic. State Machine Replication (SMR). View a server as a state machine.. To replicate the server:. Paxos Made Simple One-shot Paxos: solving consensus Multipaxos: Efficient state machine replication One-shot Paxos: solving consensus Multipaxos: Efficient state machine replication Consensus Get N nodes to agree on a value View Change Protocols and Consensus COS 418: Distributed Systems Lecture 11 Mike Freedman Today View changes in primary-backup replication Consensus 2 Review: Primary-Backup Replication Nominate one replica Consensus I FLP Impossibility, Paxos COS 418: Distributed Systems Lecture 7 Michael Freedman 2 Recall our 2PC commit problem C  TC: “go!” TC  A, B: “prepare!” A, B  P: “yes” . Oct 22, 2018. What is consensus?. A group of people go to the same place for the same meal.. → A set of nodes have the same value for the same variable.. X=. 7. X=7. X=7. Why is it important?. In state machine replication (SMR):. Paxos. COS 418: Distributed Systems. Lecture . 10. Wyatt Lloyd. Let different replicas assume role of primary over time. System moves through a sequence of views. How do the nodes agree on view / primary?.