You are a lead systems architect designing a distributed system that must maintain high availability despite component failures. Develop a comprehensive design document that addresses the following: 1) Different types of failures that can occur in distributed systems, 2) Strategies for detecting failures quickly, 3) Approaches for maintaining consistency across nodes, 4) Recovery mechanisms for different failure scenarios, 5) Methods for graceful degradation when resources are constrained. For each component, explain the theory behind your choices and provide practical implementation considerations. Include examples of how real-world systems implement these patterns and discuss the trade-offs between different approaches.