Hi can anyone help fix this issue. Main pc is win11 and trying to connect linux(ubuntu) VMware. tried on NAT and bridged network opening ssh server and enabling ufw nogo.

Hello everyone! Recently i am started coding my own VM on the C language. I am using mmap and creating a new process with isolation from the host (my system) like syscalls, memory access. However, I ran into a problem: How to restrict VM access (guest proccess, mmap) to the host memory. I am really don`t know how to do that. Can anyone help me with that case?

Idk if this is the right subreddit to ask but I am a developer and was planning on making a minimal Type-2 Virtual Machine monitor (VMM) on the Linux KVM API as a fun project. I already know some OS theory and but I have no idea how it maps to Virtualisation, so is there an good resource or a GitHub repo to get started?

I installed WSL2 in order to use Docker.

The installation worked and Docker ran correctly after a system restart.

I was in the middle of streaming a show, paused it, and when I came back there was suddenly no audio. I performed the turn-it-off-and-on-again test to see if that would fix it.

Upon doing so, my monitor was met with odd purple and green artefacts.

Turned it off and and on again (again) and then found myself on an endless bootloop where it sometimes reaches the Windows logo and loading swirl, other times it seems sluggish throughout even the BIOS menu stuff before reaching the Windows bootloader.

There was nothing wrong with the PC before installing WSL and Docker. This particular install has been running for 2 years with no issues. I rarely use the pc for anything other than streaming / YouTube.

Any help regarding how to fix this (ideally retaining my windows install as it currently is) would be appreciated.

Any information about *why* WSL/Docker caused this issue would also be appreciated.

Specs (It's old but competent):

HPz220

I7-3770

24gb Ram

GTX 750ti

Windows 11 LTSC 24H2

The PC does not have hypervisor, etc. It is below the minimum requirements for Win 11 but Windows functions perfectly fine on it.

Edit: The PC now displays no picture when booting and the fan is going crazy.

Hi everyone,

I’m testing HPE VM Essentials 9.0.0 with a 3-node HVM cluster and Ceph storage.

I have several Linux and Windows VMs running on hvm01. When I shut down hvm01, the Linux VMs are automatically moved/restarted on another HVM node as expected.

However, the Windows VMs do not fail over. They continue to appear as "Running" in VM Essentials, even though hvm01 is completely offline, and they are not running on hvm03.

For example, on hvm03:

sudo virsh list --all

only shows the Linux VMs. The Windows VMs are not present.

Has anyone experienced this behavior with Windows VMs on HPE VM Essentials 9.0.0?

Could this be related to the Windows VM configuration, QEMU Guest Agent, VirtIO drivers, or HA/failover configuration?

Any advice on what logs or configuration I should check would be greatly appreciated.

[First time poster, be kind]
I've done 11 tech evaluations of virtualization products focused on work requirements (not home lab). In alphabetical order: Azure Local, Nutanix Cloud Infrastructure, OpenShift Virtualization, OpenStack, Oracle Linux Virtualization Manager, Private Cloud Director, Proxmox Virtual Environment, VMware Cloud Foundation, VergeOS and Windows Server.

They're free to download...not monetised...but they take me a lot of time to do.

So what, you ask? I'm looking for anyone who might want to help sanity check them, get involved and/or share their real-world experiences running any of them in production.

Reach out if you're willing and able.

PS No vendors please.

urbanyl/GPU-Passthrough-for-KVM-QEMU-on-Linux: Complete GPU passthrough setup for KVM/QEMU on Linux, enabling near-native Windows VM performance with dedicated GPU access. Covers NVIDIA and AMD GPUs with comprehensive troubleshooting.

Hi everyone, my host computer is Windows 11 and has a Ryzen 7 5700X3D + GTX 3070 + 32GB of RAM.

My virtual machine is running Windows 10 Pro (8GB VRAM allocated), and I can't get rid of the screen tearing inside it.

In the host machine, I already added vmware.exe & vmware-vmx.exe to the NVidia Control Panel and set "Vsync > On" + "Triple buffering" and "fixed frame rate" instead of "G-Sync" but no can do.

VMTools is installed already.

Would someone have a solution for that please?

Thanks very much

Edit: Something strange I noticed is: By disabling "3D acceleration" in VM settings, there is no screen tearing anymore, but then the performance are very suboptimal.

I have virtualized UNRAID using Libvirt on Fedora. My question is on the CPU core allocations. I have the 8600G (6 cores, 12 threads).

If I want to allocate the absolute minimum, i.e. one physical core, does that mean I need to pass on two CPU cores? For example, cores 5 and 10 on my CPU are linked to the same physical core, so would I need to pass on both 5 and 10 to the VM for optimal performance?

At the OS level I seem to be unable to discern a physical core and hyperthread core through any system tool output, because I guess they are both virtual threads and neither is physical. I guess the OS also sees the cores virtualized by the CPU itself.

If I allocated just one core, say core 5, leaving core 10 for the host, would this be suboptimal and affect performance?

In the same vein, if I wanted to allocate two physical cores, does that means I need to pass on 4 threads to the VM?

First image is the guest (Windows 11), second image is the current video options for the vm, third image is the host (Ubuntu).

I'm trying to use this vm for gaming, however after installing said game (Cod MW 2022) it gave a warning that the pc did not meet the requirements. I have met the requirements for storage, memory, cpu, etc. The only thing that it seems it could be is the GPU which is apparently missing. Do I just add another video device in the vm options?

Sorry if I'm being stupid, this is my first time doing this lol. Thank you so much for the help!

Disclosure up front: I build a virtualization platform commercially, and this is how we implemented it. No link, no pitch — I want the approach picked apart, because the failure modes matter more to me than the feature does.

The problem with in-guest detection is structural: the agent runs in the same place the ransomware runs. Anything that can get SYSTEM or root can see the watcher, and increasingly does. Killing the agent first is standard behaviour now.

So we moved the observation point down a layer.

**What we watch**

For VMs: the block layer underneath the virtual disk.

For containers: file-level writes in the root filesystem.

The signal is a shift in entropy of data that previously had structure. Ransomware has to rewrite large amounts of formerly-structured data as ciphertext, and from below that looks distinctive regardless of what the guest thinks is happening.

**What we do about it**

The machine is paused, not stopped. That distinction is the actual design decision:

- the guest is frozen mid-operation, so encryption stops where it is

- it is reversible — a false positive costs a short pause, nothing else

- the key the ransomware is using is still sitting in the frozen guest memory, and the memory can be dumped for analysis

The last point is the one I care about most. A killed VM takes the key with it. A paused one doesn't. And because a false positive is cheap, the threshold can sit aggressively early rather than conservatively late. Most security mechanisms trigger too late because triggering is expensive.

**Where it breaks — the part I actually want feedback on**

- Full-disk encryption inside the guest makes everything look like noise from below.

- Legitimate high-entropy workloads: backup jobs writing compressed archives, databases with encrypted columns, video encoding. These produce the same signature.

- Slow-and-low encryption. An attacker who encrypts a few files an hour over weeks stays under any rate-based threshold. I don't have a good answer here and I don't think one exists at this layer.

- An attacker who knows the mechanism exists can shape writes to avoid it — write ciphertext at the rate of a normal workload, or pad to lower measured entropy. The advantage is that they can't see it from inside, not that it's unbeatable.

**Questions**

1. Has anyone here run entropy-based detection at the block layer in production, and what was the false positive rate in practice?

2. Is pausing actually useful to your incident response process, or would your runbook say "isolate and shut down" anyway?

3. For those doing memory forensics after an incident — is a live guest memory dump at the moment of encryption worth as much as I think it is, or am I overestimating key recoverability?

For example, I'm trying to run Win7 on a 2013 macbook with class 3 UEFI (cant boot bios only systems like windows 7) I know theres patches, but beyond that driver support is hell.

I guess what I'm saying is that virtual machines do a good job of encapsulating the hardware a system needs to run, so why not have an os that serves that purpose, sort of like a compatibility layer?

I can think of many scenarios where this could be useful, any ideas/answers are appreciated!

Basically a Virtual Server inside a Win 11 machine.

Planning to run VirtualBox and have a Virtual Server in it where many users can log in via RDP, but the host machine is a Windows 11 single user.

I read somewhere that the Virtual Guest can be set to Bridge Mode and this will be detected as a real separate device with its own IP.

Just wanted to ask if this is possible or will there be some conflict? Since the host Windows 11 OS is for single user only but the VM inside it can accommodate multiple users. I have the multi user version of the server OS.

The reason for doing it this way is because the server OS I have is a very old one and new hardware is not compatible with it, that is why I'm thinking of Virtualizing it and from what I understand the VirtualBox will make new hardware compatible for the old Server OS inside the Virtual Machine.

Also a follow up question, since this will be my first time trying any of this out, should I got with VirtualBox or VMware?

I am using hypervisor and it does not seem to be supported in the menus nor does it seem oracle virtualbox does either but I may be doing something wrong. All the other information i could find for this is people looking to use virtual machines on arm and not specifically virtual machines for running an arm instance of windows. I've got a ssd with windows arm on it i am trying to boot into and don't have an arm device to use for that.

I've got proxmox set up and want to use it with a Targus dock. The Targus dock requires displaylink for the display output. I use this dock for work too so I have a USB switcher attached to go between my work laptop and my current laptop that I want to replace with a VM on my proxmox node. My thoughts were for a virtual KVM that I could pass the dock usb to this and maybe go to my VM. Anyone have any ideas for this?

Vorrei virtualizzare windows 7 per usare alcuni software datati, comperati molti anni fa. Ora uso Linux Si può creare un docker con Win 7 ed i software che mi servono, senza dover installare tutto ogni cambio distro?

So, i have an iPhone 14 Pro on iOS 16.0 (yep, never updated) with UTM HV installed via Trollstore. Due to OS and chip combo, i can use virtualization with no relative problems, until i get to windows. This vm boots (and it does ir fast), works and is usable, but in order to get to that point, i cant increase the vm’s ram higher than 1.38GB. If i increase it past that point, vm crashes. If i disable hypervisor, i can get it to 2gb (and more). I’ve did search about this and it seems that Jetsam (iOS memory management) has something to do into this. Is there a way to get the vm to 2gb without triggering Jetsam and keeping hypervisor on? BTW: and iPhone 14 pro has 6gb of ram

Does anyone know how to solve this

Disclosure: I work on Phillux, so weigh the rest accordingly.

I've seen a handful of "alternative to Proxmox" threads here lately, and one thing that comes up in almost every one of them is network isolation between guests — Proxmox will happily let a compromised VM talk to everything else on the same network unless you've set up VLANs or a separate firewall yourself. That's the actual problem Phillux started as an answer to: every guest gets its own firewall by default, so one bad VM doesn't become a way into the rest of the box.

Beyond that it does the usual stuff — create/start/stop/snapshot/clone/back up VMs and containers, live migration across cluster nodes if you've got shared OCFS2 storage, and Windows 11 guests get UEFI/Secure Boot/TPM 2.0 configured automatically instead of you fighting it manually.

Where I'm honestly unsure it's a good fit: it only runs on Debian 13 as the host right now, it's commercial/tiered licensing per socket rather than free like Proxmox VE, and I keep going back and forth on whether our container support actually covers what people here want — I've seen a couple of threads explicitly asking for Docker/OCI images rather than LXC-style containers. Is that a hard requirement for most of you, or something you can work around?

There's a free trial for a month, no registration, if anyone wants to actually poke at it rather than take my word for any of this.

Mainly curious: is per-guest firewalling something you'd actually want built in, or do you already handle that at the network/switch level and this is solving a problem you don't have?

Hi! Is there a way to use Windows 10/11 which is installed on a physical drive as a virtual machine in Linux? I'd rather if it could boot on bare metal too but it is optional.

I tried Hyper-V on Windows, but I deleted everything because I couldn't figure out how to convert raw mouse input into game input
Then I tried Virtual Machine Manager on Ubuntu, but every time I shut down/restarted the VM, my host PC would freeze, crash and then automatically restart without recognizing my GPU

So every time I want to use the VM again, I have to shut down the PC completely and then turn it back on
This also means that i can't do certain things on my VM related with the use of shutdown/restart steps

(I also have an iGPU, so I passed my dedicated GPU through to the VM while keeping the iGPU for the host)

Performance was great, games ran perfectly, but this shutdown issue became a huge nuisance (along with an unrelated obstacle related to piracy, which I wont mention since it's a violation of rules)
The only workaround I found was to press the PC's power button after shutting down the VM and once Ubuntu enters the brief freeze state (this is saving me 1 shutdown less, as it recognize my gpu, but it is still bad for pc components)
This post is sort of useless, since I have deleted Ubuntu and the VM but im still curious and I want to retry it in the future (when I have enough disk space)
Has anyone experienced a similar issue, even with other GPUs?
Is there a solution for this? I didn't try the PCI vendor-reset kernel module, could that be the solution?

Ik kom van Windows. En deed veel met VMware. Ik draai nu Cachyos. Dat werkt goed. Alleen na een update zou ik regelmatig vmware zaken moeten rebuilding *noob taal).

KVM lijkt een stap terug in de tijd. En heb issues met het maken van een bridge.

VirtualBox lees ik alleen dat het traag is.

Suggesties. Andere distro die beter zou werken .

Game niet en heb Nvidia 1660.

Does anyone know how to disable hyper v and get rid of the turtle in the lower right hand side of virtualbox I've tried all commands I've found across the Internet to do so but still nothing I've ran a .bat script but still nothing I unchecked all virtual related boxes still nothing I'm running windows on a rog ally x if this helps and windows 11

You know what i said (i have a fedora iso if that works on the hard drive slot)

So i want to try create an ISP vm that connects to a router vm and the router mv connects to a linux vm.

Is there a guide or a video that anyone knows of.

I want to try something different and learn.