I need a sanity check. I’m a graybeard who’s been managing ESXi for years, but thanks to the Broadcom situation, we’re being pushed toward Hyper-V.

I’m currently building out a test cluster so we can validate migration, performance, and general behavior before we go any further.

I have six hosts total, with four built so far. I’m presenting three VLANs to the hosts:

• VLAN 65 – Management
• VLAN 66 – Cluster communication
• VLAN 67 – Live Migration

Networking is being deployed through SCVMM using logical switching on top of a SET switch. Each host has three vNICs, one for each VLAN.

VLAN 65 is fully routable and has the default gateway. VLANs 66 and 67 are currently L2-only with no gateways. They’re intended strictly for cluster traffic and Live Migration.

The cluster networks are configured like this:

• 65 = Cluster and Client
• 66 = Cluster Only
• 67 = Cluster Only, with Live Migration restricted to this network

I also had to add firewall rules to allow cluster communication between the VLANs using both IPv4 and IPv6. Apparently Failover Clustering still makes use of IPv6 internally even when IPv6 is otherwise disabled. Once the hosts are already members of the cluster, everything appears to work normally.

The problem is joining new hosts to the failover cluster.

If VLAN 66 and 67 are enabled on the existing cluster nodes, a new host will sit there trying to join for roughly 15 minutes and eventually fail. If I disable the 66 and 67 interfaces on the existing nodes, the new host joins the cluster almost immediately.

Once the host is joined, I can re-enable 66 and 67 and cluster communication seems to work fine.

What I’m trying to figure out is what I’m missing here. Even if I change the cluster roles so 66 and 67 aren’t being used for cluster communication, the join still fails as long as those interfaces are enabled.

Do VLANs 66 and 67 actually need to be routable for the initial cluster join? I could make them routable, but I still wouldn’t put default gateways on those interfaces, so I’m not sure how that would help if the join process is trying to reach domain services or something else outside those subnets.

For a long time, I used the PowerShell script “get-HyperVReport” to quickly get an overview of my Hyper-V clusters in HTML format. Unfortunately, this script no longer worked properly on Windows Server 2022 and 2025.

Since I didn’t want to do without the reports, I forked the script and fixed the bugs I was aware of.

Maybe the revised script will be helpful to some of you:
https://github.com/martin-zh/Get-HyperVReport

So about couple months ago i started using a vm to run extra instances of diablo2. For some reason after i started using hyper v my internet connection on host randomly times out and disconnects after about 1-2 hours. Only a restart of my host pc resets this to get my internet connection back. While running a vm the internet connection maintains within the VM but host loses network. Ive tried making new network switches but it still does the same thing. Ive also went into my network adapters to make sure they dont auto power off after a time but that doesnt seem to be the issue. Why would my host lose network but vm keeps it? This now happens even if not running hyper v vms. Ive thought of doing a factory reset but worried about losing personal info and passwords. Anyone know what could be causing this? Any ideas would be welcomed!

Hello im trying to make a windows 11 vm and im worried i have a crap win 11 iso. I just want it to run diablo2 ressurected on but must be win11. my iso image boots with tpm unchecked but in order to install win 11 on a vm you need tpm checked in vm settings. After closing the vm checking the tpm box in settings it just wont launch the vm. Something about that setting wont let it boot up. My host has win11 so i have the 2.0 it needs. Anyone have issues with this ever and can offer solutions?

Hi Fam,

I had a weird issue this morning and would like to understand it better.

I have a Hyper-V cluster with 3 nodes and around 24 VMs running on it. One of the nodes froze because the RAID controller failed/disappeared for some reason. The Hyper-V cluster then started having problems and eventually quarantined the problematic node.

I was under the impression that if a node is down, unresponsive, or stuck, the cluster would automatically move the workloads to the other nodes. I had already verified this during live migration and failover testing, and yes, when I take the host down normally, the load is distributed automatically.

The issue is that the Windows VMs running on that node also became stuck. I wouldn't say they crashed, because "stuck" is probably a better description. After the host was rebooted, all of those VMs went through CHKDSK and eventually came back up.

Now I'm in a somewhat unreliable situation, and I'd really like to understand what could have caused this and how I can prevent it from happening again.

What could be the main reason for this behavior, and what should I check or correct?

I have an old Dell R210 running Server 2022 that I would like to migrate the OS to run as a VM under HyperV on a Server 2025. I'm fairly familiar with most other virtualization schemes, just new to HyperV. I first tried with Disk2VHD and got what appeared to be a valid VHDX, but when I tried to run it on the 2025 server, I got an odd screen here.

Somebody suggested using the Starwind v2v converter, which I tried, which gave a different file size for the output vhdx. Tried that one, got the same error msg as above. The vm on the 2025 system was set up as a "generation 2" vm. I'm puzzled by the message being a bit less than helpful.. But it IS a microsoft product, so I guess its expected.. The vhdx is at D:\VM and that is where the vhdx is listed in the HyperV configuration page. What am I doing wrong??? Help?

We are launching a Windows .NET application to a pilot group of users and it is presently unsigned.

Many of the users can install it OK (regardless of the unsigned status) but one user reported it was blocked by Smart App Control. He was able install it after temporarily disabling SAC, but the install was still partially ineffective.

I want to test a SAC block myself to improve the app's behaviour, but I cannot get it to block our app - or any other app for that matter. I have followed the guidance here:
https://support.microsoft.com/en-US/Windows/Security/Threat-Malware-Protection/smart-app-control-frequently-asked-questions

I am installing Windows 11 Pro in a Hyper V VM. SAC is set to "ON". Confirmed Secure Boot, TPM enabled etc. and a number of troubleshooting steps on conjunction with Claude that were suggested specifically for virtualisation.

I am not in the USA, but the user in question is. I'm starting to wonder if the state of Microsoft's SAC-rollout is not complete, globally. I'm after some guidance for ways for me to test that SAC IS actually taking effect on my VM, so I can reason why our app does NOT currently seem to be blocked on the same VM.

Yes - I know we need to focus on getting the app signed, this is happening in parallel to my investigation. And yes, I know it's unusual be actively trying to simulate a block, but I really want to replicate what our user is experiencing and see it with my own eyes.

Any suggestions appreciated.

Has anyone had any luck getting UR4 installed on their 22 SCVMM box? The catalog page is empty and the roll up released in July. We’re having a lot of sql errors that it’s meant to fix, but I’ve had not luck finding it. I’ve opened a ticket but so far I’ve heard nothing back.

Catalog: https://www.catalog.update.microsoft.com/Search.aspx?q=5098585

Info page: https://support.microsoft.com/en-us/servicing/management-tools/virtual-machine-manager/update/2026/07/update-rollup-4-for-system-center-2022-virtual-machine-manager

UPDATE: the patch is available now

I’m new to Hyper-V and I’m wondering about the best way to setup our Backup infrastructure with Veeam Backup and Replication.

So far, we were using VMware. Our setup usually looked like this:

- ESX Hosts and vCenter are in a Management VLAN/Subnet

- Backupserver is in Backup VLAN/Subnet

- ESX Hosts have an additional VMkernel Adapter with an IP address within the Backup VLAN/Subnet

- Backup Server has entries in its Host file, pointing the hostnames of the ESX hosts to their IP address in the Backup subnet 

That way, restore operations are not routed and go directly over layer 2. How would a comparable setup look in Hyper-V?

I'm working on one of those one-click "easy-gpu-pv" scripts, but this one is for running GPU accelerated Linux guests under regular Hyper-V instead of being limited to WSL2, or just CUDA.
CUDA works, encoding/decoding, OpenGL, and there's experimental Mesa support.

Ripthulhu/easy-gpu-pv-linux: Allows you to use the paravirt GPU inside of a hyper-v linux guest

Having trouble re-joining a host back to a cluster, hoping someone can give me some insight because I cannot find many similar issues:

One node (call it Node A) cannot rejoin the cluster after being drained/rebooted for routine maintenance. The other two nodes are completely healthy, holding quorum, roles all online. Node A's Cluster Service runs locally but every join/form attempt ends the same way:

Get-ClusterNode shows Node A stuck in Down state (occasionally rolls back to no record at all)

Cluster log: repeated [QUORUM] Fail to form/join a cluster in 6-7 minutes → FatalError: join/form timeout (status = 258) (WAIT_TIMEOUT)

Live event log: Event 1650 (lost/established UDP connection on the management endpoint) and Event 5417 ("Cluster Service has terminated due to a fatal error... Error Code: 3473458" = ERROR_CLUSTER_JOIN_ABORTED), repeating in a loop

The NetFT pseudo-adapter (Microsoft Failover Cluster Virtual Adapter, shows as Local Area Connection* N in Get-NetAdapter -IncludeHidden) cycles Disconnected → Up → Disconnected on an irregular ~10-150 second cadence, indefinitely

Meanwhile vEthernet (Management) underneath it stays Up continuously the entire time — confirmed via a parallel live polling loop. NIC RX/TX counters on the same adapter climb steadily throughout, never stalling

Hi everyone,

I'm hoping someone can help me figure out a really frustrating input issue.

My Setup: I have a Windows 11 Pro desktop running Hyper-V. I remote into this host using Parsec from my Android tablet. On this host, I am running two VMs: one Windows 11 VM and one Ubuntu VM.

The Problem: When I remote into my host via Parsec, all touch inputs and clicks work flawlessly. Furthermore, when I open my Windows 11 VM, everything is also completely fine – clicks and movements pass through directly from the tablet without a hitch.

However, as soon as I open my Ubuntu VM (using Hyper-V's VMConnect), the mouse movements track perfectly inside the VM, but mouse clicks do absolutely nothing.

What I have tried so far to fix it: I suspect this is a clash between Parsec's input injection and Hyper-V's Basic Session synthetic mouse driver for Linux. Here are the solutions I have attempted:

1. Tried switching from Wayland to Xorg: I edited /etc/gdm3/custom.conf and /usr/lib/gdm3/gdm-daemon.options to disable Wayland. I also made sure xorg and gnome-session-x11 were installed. Despite this, the gear icon refuses to show up on the login screen, so I couldn't manually select Xorg.
2. Attempted to enable Enhanced Session Mode: Since RDP (Enhanced Session) handles Parsec inputs perfectly on my Win 11 VM, I tried to replicate this on Ubuntu. I installed xrdp, linux-tools-virtual, and linux-cloud-tools-virtual on the Ubuntu guest and started the xrdp service.
3. PowerShell configurations: I tried forcing the transport type via PowerShell on the Windows host using Set-VM -VMName <name> -EnhancedSessionTransportType HvSocket.

Despite all of this, the "Enhanced Session" button in the VMConnect View tab remains completely greyed out for the Ubuntu VM.

Has anyone experienced this specific Parsec + Ubuntu Hyper-V click issue, or does anyone know what I might be missing to get Enhanced Session working on Ubuntu so the clicks will finally register?

Thanks in advance!

Hey it seems MS took at least one suggestion out of https://www.reddit.com/r/HyperV/comments/1o9siyz/comment/nk83qgb/ . It's the smallest QoL fix ever but who would have expected we would get an update 😄

Found this on Windows Insider builds (29639.1000), you can enable it with the following but it'll likely come in the next release or something:

.\ViVeTool.exe /enable /id:55721547

I was watching normally YouTube Video. Suddenly out of nowhere bluescreen appeared as shown in the image above 👆.

In 4-5 years of my laptop time this is the first time I saw this issue, earlier I have had a bunch of issues but never as bad as this. The black screen appeared then. None of my keyboard keys are working I tried using caps or f12. Only forced power off is working on is not happening like the Dell logo never comes hence f12 ain't working either.

I also observed that there is this constant flickering of light the one in which I plug my charger pin in a particular pattern as mentioned below 👇

Orange(Amber), Stop, Orange(Amber), Stop, (White, Stop)*4 times and then again orange stop combo 2 times then again white Stop 4 times and so and so on.

Now I'm not much of a hardware person. Had it been any software issue I might have gave it a try. What I'm concerned about mostly is how costly it would be. Could it be motherboard issue, socket, ram, driver update or any other software related issue.

Also a point to share as shown in the attached image. It also flickers at the top of the screen. As shown in the image attached. I'm a college student and Oh Lord hopefully the cost for this issue won't be much. If it costs more than ₹1,000 INR, I won’t even be able to afford it.

Greetings!

I'm replacing a standalone workgroup 2016 Hyper-V server with a new 2025 host. I was hoping to utilize shared-nothing Live Migration for a zero-downtime move of the VMs, but turns out they need to be joined to an active directory domain, according to the error I received when trying to enable it in Hyper-V Manager.

That said, is there any way around this without joining the hosts to Active Directory, or possibly a third-party solution that can facilitate a live migration?

I've played with Starwind Converter, and though it works well, it still required the source VM to be shut down and destination VM to be powered on. Not a live no-downtime method.

I'm beginning with virtualization. I have a PC with Windows 10 Pro that can't be upgraded to Windows 11. I installed Hyper-V on it and created two VMs: one with Windows 10 Pro to install and practice automation software like PLCs, SCADA, and DCS; and the other with Windows Server 2025 to install a free and open-source CRM (Dolibarr) and possibly Odoo. I also want a third VM with Windows Server 2025 to create and manage databases, which would only have local network access for other users.

In Hyper-V, I created three switches: internal, external, and private.

For the Windows 10 Pro VM, I only want it to connect to the host PC, so I configured it as an internal network. For the Windows Server 2025 VM, I configured it as an external network so it can have a web server and everything necessary for CRM users to access it on the local network and/or from the internet.

The issue is that none of the three switches, nor the Hyper-V DefaultSwitch itself, have internet access. It was necessary to create a bridge on the host PC between the host's network card and the virtual network card of each VM.

I can access the internet from the host PC through my internet service provider's router, which have a Class C local network.

I appreciate everyone's valuable assistance in providing clear guidance on how to configure both the host PC and Hyper-V, as well as each VM with the required components.

My background is not in IT, but in electrical engineering, so I'm just starting out with network and server installation and configuration. I'm doing this out of necessity for the startup my wife and I started.

I recently installed Pihole on an Alpine Linux VM via HyperV and am routing my network traffic through it with my router. This is all working great EXCEPT my desktop with the host OS can't access the web interface for Pihole and doesn't seem to be routing its traffic through Pihole either. Every single other device on my network is working as expected (CAN access the web interface and is being recognized as a client).

Attached is the virtual switch the VM is operating with

Any ideas?

Всем привет. Терминальный сервер на виртуалке Hyper-V (Windows Server 2025), внутри Хоста на Windows Server 2025 спустя день работы начинает дико тормозить.

Дескрипторы постоянно растут. Показатели железа в норме. Грешил на сеть, потом на настройку ВМ.

Сейчас уже и не знаю что думать. Спасает только перезагрузка.

Когда перезагружаю - первое время сервер летает. Потом возвращается к тому же состоянию.

Куда смотреть, что искать, что настроено некорректно? Почему это не работает И как это должно работать правильно? Помогите разобраться, знатоки!!!

Two HP DL560 Gen10 hosts running Hyper-V, Citrix VDI on top. We bought a T4 per host to test GPU acceleration and the idea was to split each card over multiple VMs, 4 or 8 or whatever it can handle. Later (in two to three years) we'll upgrade our environment to new servers.

Then I went to install it and got stuck (bad investigation? who can say but fugg me). The vGPU package has no host driver for Windows Server at all, the Host_Drivers folder is ESXi and KVM stuff only? So am I supposed to run the guest driver installer on the Hyper-V host itself, or is there a separate download I'm not finding? And where do you even get the right files, is that the licensing portal only? It seems that licensing portal is not complete for Hyper-V.

From what I can find in the docs Hyper-V never supported normal vGPU, and GPU-P on Server 2025 doesn't list the T4 as supported. Which would mean DDA, whole card to one VM, is the only thing we get. Fine if that's true, I just want to be sure before I go back to my boss with it.

If DDA is the answer, is dropping the T4 into one multi session VDA and letting everyone share it inside that VM a reasonable setup, or does that fall over in practice?

Hyper-V is staying, so no ESXi suggestions please.

I'm running Ubuntu 26. How do I get the IP address of the VM to show up under Networking->IP Addresses in the Hyper-V Manager?

Looking for feedback from organizations running a 4-node Hyper-V S2D cluster (Rack Awareness enabled)

Hi everyone,

I'm interested in hearing from people who are running production Hyper-V clusters with Storage Spaces Direct (S2D) and Rack Fault Domain Awareness.

Our environment has the following architecture:

• Windows Server Failover Cluster
• 4 Hyper-V nodes
• Storage Spaces Direct (S2D)
• 2 physical racks
• 2 nodes per rack
• Rack Fault Domains configured correctly
• Storage pool configured with Rack Awareness
• 2-way mirror resiliency
• Cluster Shared Volumes (ReFS)
• Around 100+ production virtual machines
• Automatic Storage Rebalancing disabled (manual balancing only)

Networking

Each host has four physical NICs:

• NIC 1 + NIC 2: Dedicated for the Hyper-V virtual switch (SET Team) carrying VM traffic.
• NIC 3: Dedicated to storage, cluster communication and live migration.
• NIC 4: Dedicated to storage, cluster communication and live migration.

The storage/cluster network uses SMB Multichannel across the two dedicated adapters. RDMA is not enabled (standard Ethernet only).

Our primary goal was to tolerate the complete loss of one rack while keeping production online.

During a recent Disaster Recovery test, we intentionally shut down the two nodes from one rack. The remaining two nodes successfully kept all VMs online for approximately two hours before the cluster started experiencing CSV Auto Pause events, CSV draining, storage instability and eventually multiple VM outages.

At this point I'm more interested in understanding how common this architecture is in real-world production.

Some questions for people running S2D:

• Are you running a similar 4-node / 2-rack design?
• Is Rack Awareness enabled?
• Are you using RDMA, or are you successfully running without it?
• How are your storage and cluster networks configured?
• Have you ever tested losing an entire rack?
• Did the cluster remain stable indefinitely, or only for a limited time?
• Have you experienced CSV Auto Pause or storage instability after operating for an extended period on only half of the nodes?
• Would you recommend this architecture today, or would you instead deploy more nodes or another topology?

I'm especially interested in hearing from organizations that have performed real DR tests rather than theoretical discussions.

Any lessons learned, Microsoft recommendations, or production experience would be greatly appreciated.

Thanks!

I have a vSphere Windows Server 2012 VM that I took a backup of, and when I instant recover it to Hyper-V using Veeam, it's created as a Gen 1 and doesn't boot. How can I get it to be a Gen 2 VM?