CS514: Intermediate Course in Operating Systems

Conclusion?

Other options

Server replication

Primary/backup

Primary/backup

Primary/backup

Issues?

Split brain: reminder

Split brain: reminder

Split brain: reminder

Implication?

Real systems

How does hardware  help?

Reconciliation

Summary

Replication and High Availability

Steps to a solution

Non-blocking Commit

Definition of problem

Non-triviality

Typical protocol

Commit protocol illustrated

Commit protocol illustrated

Commit protocol illustrated

Failure issues

Failure model impacts costs!

Commit with simpler failure model

Commit protocol illustrated

Example of a hard scenario

Commit protocol illustrated

Example of a hard scenario

Skeen: Three-phase commit

Skeen: Three-phase commit

Three phase commit protocol illustrated

Observations about 3PC

Assumptions about failures

Problems with 3PC

Situation in practical systems?

Process groups

Failure detection

Architecture

Issues?

Architecture

Issues

GMP design

Reading ahead?