Supporting Database Mirroring sources behind a firewall
Database mirroring is a powerful feature in Microsoft Fabric, enabling seamless data replication and high availability for critical workloads (learn more about mirroring). However, connecting to mirrored databases behind a firewall requires the right integration approach. Database Mirroring now supports firewall connectivity for Azure SQL Database, with Snowflake and Azure SQL Managed Instance coming soon, ensuring secure and efficient data movement. In this blog, we explore how to enable these connections using the On-Premises Data Gateway and the VNET Data Gateway. And this is just the beginning—every new source supported by Database Mirroring will also support these gateway options, ensuring secure connectivity across your entire data ecosystem.
Enabling firewall connectivity with On-Premises Data Gateway
For organizations that need to access mirrored databases behind on-premises firewalls, the On-Premises Data Gateway provides a secure and manageable solution. This gateway allows Fabric services to communicate with on-premises data sources without exposing them directly to the internet. By installing and configuring the gateway, you can establish encrypted data transfers while maintaining compliance and security protocols. For a step-by-step guide on setting up the On-Premises Data Gateway, refer to How to access on-premises data sources in Data Factory for Microsoft Fabric documentation.

Leveraging VNET Data Gateway for Mirrored sources
For databases that reside behind virtual network (VNET) firewalls, the VNET Data Gateway offers a scalable alternative. This gateway enables Fabric services like Data Factory and Power BI to securely access cloud databases without requiring an on-premises infrastructure. With VNET Data Gateway, you can maintain network isolation while ensuring low-latency and high-throughput connections. To learn more about its capabilities in the VNet Data Gateway for Fabric and Power BI is now Generally Available announcement.

By leveraging these gateway solutions, organizations can confidently integrate mirrored databases behind firewalls into their Fabric ecosystem while maintaining security, compliance, and performance. Whether you’re working with Azure SQL Database, Snowflake, or Azure SQL Managed Instance, these gateways offer the flexibility and reliability needed to scale your data operations securely.
We are actively working to expand firewall-protected connectivity to additional mirrored sources in Fabric, ensuring enterprise-grade security and flexibility across all supported databases. Stay tuned as we continue to broaden firewall support, making mirroring even more accessible and secure.
To learn more about all that’s new with Mirroring, be sure to check out our latest blog here – Mirroring in Fabric – What’s new.