Azure VNET help required

Jaspreet Singh [C] 1 Reputation point
2021-01-31T14:31:08.82+00:00

Hi Team, I have a web app (CNC application) on azure cloud which is using azure VNET integrated web application which is effected by recent microsoft change. The size of the linked subnet should contain not less than 32 IP addresses (mask /27), but unfortunately they have only 8 IP addresses at the moment. In order to keep these Azure resources supported, we need the replace the subnets according to the latest rules. Can someone please help on this.

Azure App Service
Azure App Service
Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
7,002 questions
0 comments No comments
{count} votes

1 answer

Sort by: Most helpful
  1. ajkuma 22,841 Reputation points Microsoft Employee
    2021-02-01T19:02:52.72+00:00

    @Jaspreet Singh [C] ,

    To better assist on this, could you please confirm if you have hosted the WebApp(website) on an Azure VM or App Service WebApp? Could you please share any blog/Azure doc on the changes you’re referring to for subnet and IP address size?

    For regional VNet on App Service - The feature requires an unused subnet that's a /28 or larger in an Azure Resource Manager VNet.

    Just to highlight on App Service, the VNet Integration depends on use of a dedicated subnet. When you provision a subnet, the Azure subnet loses 5 IPs from the start. One address is used from the integration subnet for each plan instance. If you scale your app to four instances, then four addresses are used. The debit of 5 addresses from the subnet size mean that the maximum available addresses per CIDR block are:

    /28 has 11 addresses
    /27 has 27 address