Hello @azure architect with .net expereince ,
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If you are using ExpressRoute, it would be possible to access the On-Premise SQL Database from the App Service by using regional VNet Integration as this enables your App to access resources across Azure ExpressRoute connections. You can also use App Service Environment.
Using regional virtual network integration enables your App to access:
- Resources in the virtual network you're integrated with.
- Resources in virtual networks peered to the virtual network your app is integrated with including global peering connections.
- Resources across Azure ExpressRoute connections.
- Service endpoint-secured services.
- Private endpoint-enabled services.
Refer : https://learn.microsoft.com/en-us/azure/app-service/overview-vnet-integration#regional-virtual-network-integration https://learn.microsoft.com/en-us/azure/app-service/environment/app-service-app-service-environment-securely-connecting-to-backend-resources
Similar questions for your reference: https://learn.microsoft.com/en-us/answers/questions/179143/index.html https://learn.microsoft.com/en-us/answers/questions/161688/index.html
Kindly let us know if the above helps or you need further assistance on this issue.
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