Multi-tenant SaaS request flow on Azure routes client requests through Front Door and Application Gateway to App Service, where tenant resolution identifies the customer and retrieves metadata. The Tenant Resolution Service queries the Tenant Metadata Database, then App Service securely accesses tenant-specific SQL databases using credentials from Key Vault, with all operations monitored via App Insights. This three-layer architecture—Internet, Azure, and Data—demonstrates how to isolate tenant data while maintaining a single application codebase. Fork this diagram to customize tenant routing logic, add caching layers, or integrate additional Azure services like Cosmos DB. The sequence illustrates best practices for SaaS isolation, least-privilege key management, and observability across the request lifecycle.