Replication

consistency models

Replication Protocols

Sequential consistency

Remote-write Protocol

  1. Write request
  2. Forward request to primary
  3. Tell backups to update
  4. Acknowledge update
  5. Acknowledge client that write complete

Local-write Protocol

  1. Write request
  2. Move item X to new primary
  3. Acknowledge write completed
  4. Tell backups to update
  5. Acknowledge update

Active Replication

Quorum-based Protocol