Lecture 7: Fault Tolerance: Raft (2)

• Why not longest log as leader?

• example vot yes only if high log entry
• AE Reply
• Persistent
  • log
  • correct Term
  • voted For
• synchronize disk update - persisting
  • write(fd, _)
  • fsync(fd)

• storing a log
  • snapshot every once in a while for efficiency

• linearizability
  • linear execution history
  • operations that finish first, and reads must come after start of writes
• reads and writes in lineariable order
• not linearizable - has a cycle