Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Hybrid Connections**: Relay-based connectivity from App Service/Function to on-prem. Uses Azure Relay; outbound from on-prem. **Limitations**: Max 100 connections per app. Not for high throughput—Relay adds latency. No VNet integration; not for large data movement. Each...
Hybrid Connections: Relay-based connectivity from App Service/Function to on-prem. Uses Azure Relay; outbound from on-prem. Limitations: Max 100 connections per app. Not for high throughput—Relay adds latency. No VNet integration; not for large data movement. Each connection is point-to-point. When to use: Quick setup for low-volume access (e.g., call on-prem API). When not: High-throughput ETL, bulk copy. Use VNet integration + ExpressRoute/VPN for that. Best practice: Hybrid Connections for legacy, low-volume. Plan migration to VNet integration for production data pipelines.
Pro-Move: 'We used Hybrid Connections for a legacy API—5 req/min; migrated to VNet integration when we added a 10GB/day ETL job.' Red Flag: Choosing Hybrid Connections for bulk data—wrong tool; use SHIR + VNet.
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