Hello @Azure ,
Apologies for the delay in response.
Hyper-V NAT switches do not come with any NAT rules by default. This means no traffic can route from inside the NAT IP range to an outside IP range and vice versa. This basically means any VM on the NAT IP range is unable to communicate with any VM, Server, or network device outside of the NAT IP range. They even are unable to communicate on the internet. A solution to this is to configure NAT networking so that VMs can access the Internet with the host NATed public IP and also routing to enable connectivity to other VMs in Azure.
Reference : https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/user-guide/nested-virtualization#networking-options
Some blog articles for futher reference :
https://azurecloudai.blog/2019/12/16/how-to-enable-internet-and-vnet-connectivity-for-nested-vms-in-azure/
https://www.thomasmaurer.ch/2017/07/how-to-setup-nested-virtualization-in-microsoft-azure/
Kindly let us know if the above helps or you need further assistance on this issue.
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