FAULT TOLERANT SERVICES
Fault-tolerant services are designed to continue operating even in the presence of failures. They are essential for maintaining high availability and reliability in distributed systems. Fault tolerance involves several strategies and mechanisms to detect, isolate, and recover from failures without interrupting the service.
- Redundancy: Multiple instances of critical components to ensure there is no single point of failure.
- Replication: Duplication of data and services across multiple nodes or data centers.
- Failover: Automatic switching to a standby system when the primary system fails.
- Load Balancing: Distributing incoming traffic across multiple servers to prevent overload.
- Isolation: Ensuring that failures in one component do not affect others.
- Error Detection and Recovery: Identifying and recovering from errors quickly.
Strategies for Fault Tolerance
- Active-Active Configuration: All nodes are active and can handle requests simultaneously. If one node fails, others continue to serve the traffic.
- Active-Passive Configuration: One node is active, and the others are on standby. If the active node fails, a standby node takes over.
- Consensus Algorithms: Protocols like Paxos or Raft to maintain consistency and coordinate actions among distributed nodes.
- Circuit Breakers: Mechanisms that detect failures and prevent the system from making calls to a failing service.
- Health Checks: Regularly checking the health of components to detect and respond to failures.