Resilience Testing Plan for Hyperledger Fabric Network

Resilience testing is crucial for ensuring that your Hyperledger Fabric network can withstand failures and disruptions. Here’s a high-level test plan for resilience testing of your Fabric network with the described infrastructure[Two Node/Docker swarm/K8s] . Please note that this is a general outline, and you may need to adapt it to your specific network configuration and requirements.

These scenarios are intended to test the robustness and adaptability of your Fabric network in the face of potential disruptions or changes. They may not be applicable to all Fabric deployments, and their execution might require careful planning and coordination. Be sure to adapt these scenarios to your specific network setup and requirements.

1. Objective

• The primary objective is to test the resilience and fault tolerance of your Hyperledger Fabric network under various failure scenarios.

2. Test Environment

• Describe your test environment, including the two EC2 instances, their configurations, Docker Swarm setup, and network details.

3. Test Scenarios

A. Node Failure Testing

  - **Scenario 1: Orderer Node Failure**    
     - Simulate the failure of the orderer node (e.g., stop the Docker container). 
     - Verify that the network can continue to operate without issues. 
     - Check if transactions can still be endorsed and committed.

  - **Scenario 2: Peer Failure**
     - Simulate the failure of one or both peers in each organization.
     - Verify that the network can still reach consensus for transactions.
     - Ensure that the network can recover automatically when the failed peer is restored.

  - **Scenario 3: CA Failure**
     - Simulate the failure of the CA node.
     - Verify that the network can still perform identity and authentication tasks.
     - Ensure that new CAs can be added if necessary to recover from the CA failure.

B. Network Failure Testing .
Objective: How your Hyperledger Fabric network behaves when there’s a network partition, meaning the network becomes temporarily divided into two or more isolated segments where nodes in one segment cannot communicate with nodes in another segment.
Explanation: Network partitions can occur due to various reasons, such as network issues, hardware failures, or misconfigurations. In a multi-node, multi-organization Fabric network, it’s essential to ensure that even when network partitions occur, the network can continue to function and later recover when the partition is resolved.

  - **Scenario 4: Network Partition**  
     - Simulate a network partition between the two EC2 instances. 
     - Verify how the network behaves when the orderer and peers are in different partitions. 
     - Test if the network can heal when the partition is resolved.

Steps:

1. Setup: Ensure your Fabric network is running normally, with nodes in different organizations communicating.
2. Simulate Partition: Introduce a network partition by blocking or disconnecting network traffic between nodes in one organization from nodes in another organization. This can be done at the network level (e.g., using firewall rules) or by stopping network interfaces temporarily.
3. Observe Behavior: Monitor how the network behaves during the partition. Pay attention to how transactions are endorsed and ordered in both partitions.
4. Recovery: Once the partition is resolved (by fixing the network issue or re-enabling network interfaces), observe how the network recovers. Ensure that all transactions from both partitions are eventually reconciled and committed to the ledger.

C. Consensus Failure Testing

Objective: Test how your Fabric network adapts to a change in the consensus algorithm.

Explanation: Hyperledger Fabric allows you to configure different consensus algorithms for the ordering service (e.g., Raft, Kafka). Changing the consensus algorithm can be a significant event, and it’s crucial to ensure that the network can handle this change without disruption.

  - **Scenario 5: Consensus Algorithm Change**  
     - Temporarily change the consensus algorithm (e.g., from Raft to Kafka or vice versa) for the orderer. 
     - Verify that the network can adapt to the change in consensus. 
     - Switch back to the original consensus algorithm and ensure a smooth transition.

Steps:

1. Setup: Ensure your Fabric network is running with the initial consensus algorithm (e.g., Raft).
2. Change Consensus Algorithm: Temporarily change the consensus algorithm to another supported option (e.g., from Raft to Kafka) for your orderer nodes. You can do this by modifying your network configuration.
3. Observe Transition: Monitor the network as it transitions to the new consensus algorithm. Pay attention to how new transactions are ordered and committed.
4. Test Under Load: While using the new consensus algorithm, simulate a load on the network by creating and endorsing transactions.
5. Revert to Original Algorithm: After testing with the new consensus algorithm, switch back to the original consensus algorithm (e.g., from Kafka to Raft).
6. Observe Transition Back: Monitor the network as it transitions back to the original consensus algorithm.
7. Verify Data Consistency: Ensure that data consistency and transaction integrity are maintained throughout the process.

D. Data Recovery Testing

  - **Scenario 6: Data Loss** 
     - Introduce data loss in one of the peers. 
     - Verify that the lost data can be recovered from other peers or the orderer. 
     - Test data consistency and integrity after recovery.

4. Performance Metrics

• Define the performance metrics you want to monitor during resilience testing. This may include transaction throughput, latency, CPU and memory usage, and network bandwidth.

5. Automation

• Whenever possible, automate the test scenarios using scripts or tools to ensure repeatability.

6. Monitoring and Logging

• Implement monitoring and logging solutions to capture real-time data during testing. Use tools like Prometheus and Grafana to monitor the health of your Fabric network.

7. Reporting

• Document the test results, including successes, failures, and any issues encountered.
• Provide recommendations for improving network resilience based on the test outcomes.

8. Recovery Procedures

• Develop and document recovery procedures for each failure scenario identified in the testing.

9. Iteration and Optimization

• Based on the test results, iterate on your network configuration and resilience strategies.
• Optimize the network to improve its ability to withstand failures.

10. Compliance Testing

If your network needs to comply with specific regulations or standards (e.g., GDPR, HIPAA), perform compliance testing to ensure it meets those requirements even in failure scenarios.

11. Scaling

Consider scalability testing to ensure that your network can handle increased loads without compromising resilience.

12. Documentation and Training

Ensure that your team is well-trained on how to respond to and recover from different failure scenarios. Document these procedures for future reference.

— — — — — — —
Conclusion :

Remember that resilience testing is an ongoing process. As you make changes to your network or deploy new versions of Fabric, it’s essential to revisit and update your resilience testing plan accordingly.