Windows Server 2019 on Hyper-V VM, Cannot Reach

Question

Specifications
Dell OptiPlex 7040

Processor Intel(R) Core(TM) i5-6500 CPU @ 3.20GHz 3.19 GHz

Installed RAM 16.0 GB (15.9 GB usable)

Product ID *removed for privacy*

System type 64-bit operating system, x64-based processor

Edition Windows 10 Pro

Version 21H1

Installed on ‎7/‎27/‎2020

OS build 19043.2364

Background

Via an administrator session, Hyper-V Manager was setup and a Windows 2019 Server VM built.
Via a user session on the same workstation, I was able to ping the server and reach it with the RDP client, Remote Desktop Connection.

Problem Statement

This was working. Then I rebooted.
Now I cannot even ping the VM.

Troubleshooting

The VM can ping the default gateway and a website, like microsoft.com.
The user session can ping the default gateway and microsoft.com.

I tried with the server's firewall turned off, but it made no difference.
I turned it back on. The server's firewall has exceptions to allow for RDP.
This setup was working. I'm not sure what changed with the reboot.

Windows Server Network Connections

Host Network Connections

My guess is the External Virtual Switch with "No network access" may be the issue.

From Hyper-V Manager, from a user session, I can connect to the server's console.
This makes sense because Hyper-V is managing the VM. When I invoke Hyper-V Manager, I'm communicating with a service, not a network.

Before the reboot, I did make the server a domain controller, known as DC1.local .

Something else to note, I can ping the server from another VM on the network.

The other VM is running RHEL on a Xen server.
This tells me that the server is reachable.
What's perplexing to me is that it isn't reachable by IP from the host.

Error Messages
None, other than failed pings.

Any ideas?

Answer 1

It was already set.

Thanks for the suggestion.

I think I may have figured it.
When the domain firewall of the server is on, I can't connect.
I need to join the workstation to the server's domain.

Answer 2

No, I still have an issue.

I can't update right now, but I'll add some tests to illustrate the issue.

Answer 3

Hello,

Thank you for your reply.

I'm glad you found a solution that works for you.

Thank you very much for your support of Microsoft products, and thank you very much for your selfless sharing.

Your sharing can expand the perspective of thinking for me and other users, and promote the continuous development of the community.

If you encounter problems in the subsequent use of Microsoft products, you are welcome to post in the community for consultation at any time.

Best regards

Zunhui

Answer 4

Hello,

Based on the information you provided, I suggest you check whether the virtual external switch has the option to allow the management operating system to share this network adapter. If it is not checked, there will be no network.

I hope the above information is helpful to you.

Best Regards

Zunhui