Azure VM nested virtualisation - Accessing Azure VNET from VM's

Question

Azure VM nested virtualisation - Accessing Azure VNET from VM's

Ben Wosjke 136

Hi all,
Looking into nested virtualisation in Azure - which has the potential to address some issues for our migration.

All the example articles talk about setting up a DHCP server on the Host and using NAT on the vSwitch.

I haven't found an article that specifically states it - but is it not possible to connect directly to the Azure VM's NIC? (like you would in an on-prem scenario) and utilise DHCP/DNS etc settings from the VNet ?

kobulloc-MSFT 26,626 Reputation points Microsoft Employee

2021-06-21T15:46:26.383+00:00
You are able to change the DHCP/DNS settings directly through the NIC resource, however Azure Lab Services has a UI wizard and a simple script available:

Enable nested virtualization on a template VM using the UI

Enable nested virtualization on a template VM using a script

Manage NICs / Change DNS servers
Ben Wosjke 136 Reputation points

2021-06-21T20:51:06.337+00:00

Hi - you seem to have missed the point of a the question.

As stated in the 1st (or 2nd) link you have provided... when creating a nested Hyper-V server - you then need to add DHCP, RRAS and create a NAT switch to the VM Host in order to provide network connectivity to the outside world - i.e. you cannot assign a VM to the base azure network connection to any of the nested VM's.

Is that correct? is there no way to connect directly to the "base" NIC for the VM's? and if yes, is that something that is being looked at - or is it "the way it is" and wont be changing anytime soon ?
Elizabeth Maher 251 Reputation points Microsoft Employee

2021-06-21T22:35:37.673+00:00

@Ben Wosjke ,

Your client VMs on your template or lab machine for Azure Lab Services will be able to access the internet, but they will not be addressable from outside the host VM. (I'm assuming you followed instructions at how-to-enable-nested-virtualization-template-vm .

Are you looking for a feature like 38458822-assign-multiple-vms-to-a-student-with-their-own-vn where students get their own set of VMs on a class network?

Have you tried Azure DevTest Labs? This service has the ability to create environments from templates that you pre-approve. You have more control over the assets than you would in a service like Azure Lab Services where the resources are hosted in a Microsoft subscription on your behalf.
Ben Wosjke 136 Reputation points

2021-06-22T01:25:16.93+00:00

wow - that's a large assumption.

I originally tagged this as "Azure-VM" and some bright spark thought they would change the tag azure labs (couldn't work out why everyone kept referring to azure labs - when what im after has nothing to do with that).

Anyway - i think its time to give up on this one - it has nothing to do a azure lab environment - its an expansion of an on-premise RDS farm, that, due to vendor specifications, has some fairly whacky requirements around it... - but this is going no-where fast.

I've added a comment to feedback.azure.com in favour of allowing mac address spoofing to virtual NICs - which would in turn (theoretically) allow an azure NIC to be exposed to a nested Hyper-V virtual switch - but will start looking for other solutions for this project.

Your answer

kobulloc-MSFT 26,626 Reputation points Microsoft Employee

2021-06-21T15:46:26.383+00:00

You are able to change the DHCP/DNS settings directly through the NIC resource, however Azure Lab Services has a UI wizard and a simple script available:

Enable nested virtualization on a template VM using the UI

Enable nested virtualization on a template VM using a script

Manage NICs / Change DNS servers
Ben Wosjke 136 Reputation points

2021-06-21T20:51:06.337+00:00

Hi - you seem to have missed the point of a the question.

As stated in the 1st (or 2nd) link you have provided... when creating a nested Hyper-V server - you then need to add DHCP, RRAS and create a NAT switch to the VM Host in order to provide network connectivity to the outside world - i.e. you cannot assign a VM to the base azure network connection to any of the nested VM's.

Is that correct? is there no way to connect directly to the "base" NIC for the VM's? and if yes, is that something that is being looked at - or is it "the way it is" and wont be changing anytime soon ?
Elizabeth Maher 251 Reputation points Microsoft Employee

2021-06-21T22:35:37.673+00:00

@Ben Wosjke ,

Your client VMs on your template or lab machine for Azure Lab Services will be able to access the internet, but they will not be addressable from outside the host VM. (I'm assuming you followed instructions at how-to-enable-nested-virtualization-template-vm .

Are you looking for a feature like 38458822-assign-multiple-vms-to-a-student-with-their-own-vn where students get their own set of VMs on a class network?

Have you tried Azure DevTest Labs? This service has the ability to create environments from templates that you pre-approve. You have more control over the assets than you would in a service like Azure Lab Services where the resources are hosted in a Microsoft subscription on your behalf.
Ben Wosjke 136 Reputation points

2021-06-22T01:25:16.93+00:00

wow - that's a large assumption.

I originally tagged this as "Azure-VM" and some bright spark thought they would change the tag azure labs (couldn't work out why everyone kept referring to azure labs - when what im after has nothing to do with that).

Anyway - i think its time to give up on this one - it has nothing to do a azure lab environment - its an expansion of an on-premise RDS farm, that, due to vendor specifications, has some fairly whacky requirements around it... - but this is going no-where fast.

I've added a comment to feedback.azure.com in favour of allowing mac address spoofing to virtual NICs - which would in turn (theoretically) allow an azure NIC to be exposed to a nested Hyper-V virtual switch - but will start looking for other solutions for this project.

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Azure VM nested virtualisation - Accessing Azure VNET from VM's

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