1. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 DISTRIBUTED SYSTEMS Principles and Paradigms Second Edition ANDREW S. TANENBAUM MAARTEN VAN STEEN Chapter 8 Fault Tolerance (Modified – Two-Phase Commit for Distributed Transactions)

2. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (1) Figure 8-18. (a) The finite state machine for the coordinator in 2PC. (b) The finite state machine for a participant.

3. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (2) Figure 8-19. Actions taken by a participant P when residing in state READY and having contacted another participant Q.

4. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (3) Figure 8-20. Outline of the steps taken by the coordinator in a two-phase commit protocol....

5. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (4) Figure 8-20. Outline of the steps taken by the coordinator in a two-phase commit protocol....

6. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (5) Figure 8-21. (a) The steps taken by a participant process in 2PC.

7. Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved. 0-13-239227-5 Two-Phase Commit (7) Figure 8-21. (b) The steps for handling incoming decision requests..