Load Balancing & Failover Intermediate

Production LLM gateways must handle provider outages, rate limits, and varying latency across providers. Effective load balancing and failover ensure high availability and optimal performance for your AI applications.

Load Balancing Strategies

• Round-Robin: Distribute requests evenly across providers. Simple but does not account for latency or capacity differences.
• Least-Latency: Route to the provider with the lowest recent latency. Optimizes for response time.
• Cost-Optimized: Route to the cheapest available provider that meets quality requirements. Minimizes spend.
• Weighted: Assign weights based on provider capacity, cost, or quality. Most flexible approach.

Failover Configuration

• Configure automatic failover with ordered fallback chains: if Provider A fails, try Provider B, then Provider C.
• Define failover triggers: HTTP errors (429, 500, 503), timeout thresholds, and quality degradation signals.
• Implement circuit breakers: after N consecutive failures, stop sending requests to a provider for a cooldown period.

Rate Limit Management

• Track rate limits across all providers. When approaching a provider's limit, proactively route requests to alternatives.
• Implement request queuing for burst traffic that exceeds combined provider capacity.
• Use rate limit headers from provider responses to dynamically adjust routing weights.

Health Checking

• Implement active health checks: periodic lightweight requests to each provider to verify availability and measure latency.
• Use passive health checks: monitor actual request success rates and latency to detect degradation in real-time.
• Dashboard showing real-time provider status, latency percentiles, and error rates for operational visibility.