Hello @wipps ,
I checked the support case and found the below update:
The engineer checked your environment and found that there is a vnet “ADDSNetwork” and two subnets named default” & “DomainServicesSubnet” respectively and there are no virtual machines in the subscription.
Azure advisor has recommended to use azure firewall to protect a subnet, so this is a general advisory if it is relevant to your setup you can implement it, and if not relevant you can ignore it.
Kindly let us know if the above helps or you need further assistance on this issue.
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