vNVMe on Hyper-V to unlock PCIe 5.0 NVMe performance
On hosts with NVMe PCIe 5.0 (E3.S/U.2), Hyper-V guests still use virtual SCSI and leave a lot of performance on the table. We are paying for top-tier storage, yet software becomes the limiter. A virtual NVMe device that preserves checkpoints/Replica/Live Migration would align guest performance with modern hardware without forcing DDA and its operational trade-offs.Enable Nested Virtualization on Windows Server 2025
Nested virtualization allows you to run Hyper-V inside a VM, opening up incredible flexibility for testing complex infrastructure setups, demos, or learning environments, all without extra hardware. First, ensure you’re running a Hyper-V host capable of nested virtualization and have the Windows Server 2025 VM on which you want to enable as a Hyper-V host ready. To get started, open a PowerShell window on your Hyper-V host and execute: Set-VMProcessor -VMName "<Your-VM-Name>" -ExposeVirtualizationExtensions $true Replace <Your-VM-Name> with the actual name of your VM. This command configures Hyper-V to allow nested virtualization on the target VM. Boot up the Windows Server 2025 VM that you want to configure as a Hyper-V host. In the VM, open Server Manager and attempt to install the Hyper-V role via Add Roles and Features. Most of the time, this should work right away. However in some cases you might hit an error stating: “Hyper-V cannot be installed because virtualization support is not enabled in the BIOS.” To resolve this error run an elevated PowerShell session inside the VM on which you want to enable Hyper-V and run the command: bcdedit /set hypervisorlaunchtype auto This command ensures the Hyper-V hypervisor starts up correctly the next time you boot. Restart your VM to apply the change. After the reboot, head back to Add Roles and Features and try installing Hyper-V again. This time, it should proceed smoothly without the BIOS virtualization error. Once Hyper-V is installed, perform a final reboot if prompted. Open Hyper-V Manager inside your VM and you’re now ready to run test VMs in your nested environment!
No SET-Switch Team possible on Intel X710 NICs?
Hello, we have lot of servers from different vendors using Intel X710 DA2 network cards. They work fine in standalone and they work fine if we create switch independet teams using Server Manager, Regardless of Dynmic or Hyper-V Port. But sadly we can't use these teams in Server 2025 because have to create SET-Switch Teams instead. But as soon as we create an Hyper-V SET-Switch Team with X710 cards, they have limited to no network communication. They still can communicate with some servers, are slow with some ohters, and can't communicate with some at all. Especially communication to other servers, which also use X710 cards with SET-Switches, is zero. SET-Teams with other cards like E810 work just fine. I've read several times that the X710 cards just wont work with SET, even since Server 2016. But I can't really give up on this, since we would have to replace a lot of them. We have tried to disable a lot of features like VMQ, RSS, RCS... but couln't make it work. Firmware and Drivers are the most recent, but it happens with older versions too. Does anyone have a solution? Thank you!
RDP connection not possible and RDS-Virtualization role comes back after restart
Hello everyone, I have here an Windows Server 2022 Standard 21H2 (Build 20348.4052) (essentials) with the newest updates. This is the Domain Controller. Hyper-V is installed with one VM. The VM is a terminal server. In the past I have tried to install the terminal server on the Hyper-V Server. To do so I have installed all kind of remotdesktop roles. This was stupid of me. Especially it does not work on a DC. I want to connect as administrator by RDP (mstsc) to the server but it does not work anymore since I have installed all these roles and features. No other users are connected. I can still connect to the VM. In one situation I was able to connect to the server but after entering the password I have received the error 0x808 (0x101) that there is no licence server for remote desktop available. I have now removed all roles related to the terminal server and the rdp which I have installed. But I can not uninstall RDS-Virtualization. After uninstalling it comes back when I perform a restart. I have already tried Uninstall-WindowsFeature -Name RDS-Virtualization -Remove In the server manager appears a menu item about remote desktop services. But there is written that no connection broker server is in the pool. The submenu server lists my DC. I have found in the eventmanager a error related to the uninstalling process 0x80070057 wrong parameter But I do not have more information. DISM /RestoreHealth and sfc /scannow did not find any problems. I am not using VDI but is maybe the Hyper-V reinstalling the role after the restart? Do I need to uninstall the role to make RDP working again or could be there other reasons? Do you know where I find a detailed log about the problems about uninstalling the role and maybe the installing? Do you have any idea how I can find out more about the problem? Thank you!
Active Directory documentation and best practices
Dear all, please, I have to fix a critical situation. I have recovered a DC VM on an old Hyper-V host. This DC is corrupted and seems that it is not working as well. I installed 2 new phisical host (cluster) with Windows Server Datacenter 2025, configured Hyper-V role, networks etc.. Also prepared (out of cluster) 2 new VM Win 2025 and I would like to prepare as new DC01 + DC02. I guess is better to configure the DC on the hosts to grant that the DC role is always available also if the cluster is not running (feel free to correct if I'm wrong, I will appreciate). I need link to video or documents to correctly perform the configuration of the new DC. The old DC are running a Windows Server 2012 R2 standard version. Is it possible to migrate to Windows 2025 datacenter ? Take note that at the end I have to assign to the new DC, the same IP address. thank you very much for your support. BR Alex.
Hyper‑V SET Loop Risk, Asymmetric Paths & Active‑Standby (ALE OXE VM Offline)
Hi everyone, Environment - Windows Server 2025 Hyper‑V - One external virtual switch - Physical NICs combined with Switch Embedded Teaming (SET) - One VM: Alcatel‑Lucent Enterprise OmniPCX Enterprise (OXE) Questions → 1) Loop prevention → 2) Asymmetric traffic → 3) Active‑Standby Problem The OXE VM intermittently becomes unreachable (no ICMP, no SIP). Hyper‑V shows it as “Running,” CPU is low, guest logs are clean. Rebooting the VM or toggling the SET team restores connectivity. Looking for advice on: - Loop‑prevention mechanisms in Hyper‑V SET - How inbound vs outbound flows are balanced - Whether Active‑Standby is possible and how to configure it - Diagnostics to confirm if asymmetric paths or loops are causing the outage Thanks in advance!
HyperV 12 on Windows 2025 ready for production?
Fighting with three HyperV servers in a failover cluster. I understand that now you have to use SET teaming and lbfo is no longer supported. I also understand that SET is still quite buggy. I have created three teams with two adapters in each of them, but it confuses me how they appear in "Network and internet > Ethernet" vs "Advanced Network setting. I have set the vEthernets to the static IPs that I need. But the way the NIC shows up seems random... Some of them shows the IP of the vEthenets and they are all set to DHCP Network seems very unstable if I use more than one NIC in a team. As far as I can google, I am not the only one having these issues. SET networking does not work stable if more than 1 NIC - correct? So if one needs an HA setup - how to handle NIC teaming correct? Can HyperV 12 on Windows 2025 be used in a prof. live setup? thx...
Untagged VLAN - Server 2025 Hyper-V
Hi, I have a strage issue and not finding a solution. Using Server 2025 with two node Hyper-V cluster. Most of the machines using VLANs which works fine. Some machines using no VLAN config. Which usually means the "Access VLAN 1" regarding our switch configuration. With Server 2019 this worked fine. With Server 2025 same NIC port, same server/NIC hardware "Untagged" VMs don't get any network connection. If I add a second NIC to the VM "Untagged" the NIC get immidiatly an IP address and has a proper connection. If I remove the first NIC, the second NIC stop working. It looks like something has changed with Server 2025 (maybe already with Server 2022). Do you have any idea what kinde of problem I have found? Thanks Jack
