1. A

    Need help with Proxmox hotplug CPU issue

    Hey everyone, I'm having an issue with hotplugging CPUs in Proxmox. Here's what's happening: Set a limit of 6 vCPUs. Launched a Windows VM with 2 vCPUs. Enabled NUMA and hotplug options in the VM settings. When I try to increase the number of vCPUs using the edit option in the hardware...
  2. C

    NUMA questions again

    I've read the NUMA wiki here: and the admin guide regarding NUMA here: however I still have some questions. * Is NUMA only useful if your PVE *host* has more than 1 physical...
  3. D

    Starting Docker Containers in unprivileged LXC on USB Hotplug

    Hello Proxmox Community, I'm using Proxmox on my home server. I have several USB Devices (DVB-S Receiver, 3D Printer + Webcam) that I want to connect to my Server and use from Docker Containers (Running minisatip or octoprint). The USB Devices are turned off most of the time and are only turned...
  4. G

    Memory hotplug prevents VM boot

    Just upgraded my testlab to latest pve no-sub. I did not install updates for 3-6 months, so no idea which one broke it. VM boots and crashes with kernel trace, as soon as I disable memory hotplug it boots just fine. Using debian cloud generic image. [ 4.912084] Hardware name: QEMU Standard...
  5. S

    vcpus: hotplug problem - you can't add more vcpus than maxcpus

    Hi When I want to hotplug vCPU and increase it, I will get below error : Parameter verification failed. (400) vcpus: hotplug problem - you can't add more vcpus than maxcpus while the "CPU limit" is unlimited . I'm using proxmox VE 7.2
  6. H

    KVM VM (64GB) won't start with memory hotplug enabled

    Hello, This had been asked several times however after extensive search there is still no real answer that would make sense or a formula that I was able to follow to assign memory - sometime it work and sometimes doesn't (guessing!) up to 48GB works fine after adding this workaround "options...
  7. U

    A new proxmox usb-hotplug service.

    Hi, After a full week of test I publish the script I made to convert my local proxmox PC to a real PC. I can plug an USB flash drive to the proxmox host and the key popup on my current KVM windows/Linux/MacOs. See the "use as a service" for a...
  8. J

    [SOLVED] FreeBSD guests boot fail

    initially my experience with Proxmox 6 was rather disturbing, eventually i resolved what caused these issues and proxmox works well for me now. Recently (yeah) though i took on myself to install FreeNAS and OPNSense which are FreeBSD based and both behave "weird". The vm config i use can be...
  9. S

    [SOLVED] Debian CPU hot-unplug error: 400 Parameter verification failed

    I just configured hotplug for CPUs and RAM on one of my VMs and have been testing it. Hotplug for the CPU and RAM work but unplug fails every time with the error: Parameter verification failed. (400) vcpus: hotplug problem - 400 Parameter verification failed. vcpus: error unplugging cpu4...
  10. B

    [SOLVED] PVE6 - CPU/MEM hotplug

    Hi, We have two PVE 6.0-x clusters with 3 nodes each. The nodes are Dell R640 servers. Both clusters are fairly new and we are in the process of installing out first VM's. The VM's are running SLES 15 SP1. As we would like to have the option of adding vCPU/RAM, we activated hotplugging on the...
  11. P

    Disable hotplug network function not working in Windows VM

    Hi there, we're using Proxmox VE since some years right now. Lately we need to disable hotplug network card functionality from Windows Guests VM because users, sometimes click in the wrong place and they do "safely remove hardware for network card"!!!! We're using the latest virtio-win driver...
  12. M

    [SOLVED] Enabling memory hotplugging results in incorrect RAM allocation?

    Hi, I have a personal Proxmox environment I use for testing, for it I use the community repo which is running the latest version of proxmox VE (5.2-2). Full package version list: proxmox-ve: 5.2-2 (running kernel: 4.15.17-1-pve) pve-manager: 5.2-1 (running version: 5.2-1/0fcd7879)...
  13. A

    Hotplug CPU

    Hi all, Im' working on PVE 5.1 and i get some issues with cpu hotplugging. I added /lib/udev/rules.d/80-hotplug-mem.rules and /lib/udev/rules.d/80-hotplug-cpu.rules file config on the node I also modified vm config file to get this: numa: 1 hotplug: disk,network,usb,memory,cpu ... When i...
  14. A

    USB hotplug on pve 5.1

    Hi all, I'm using PVE 5.1-36 and i get some issues with usb hotpluging. Is there a way to hotplug an USB key to a VM without shutdown/reboot? I know that i had to add some config files on the node to enable hotplug RAM and hotplug CPU. Is this the same for usb hotplug? I tried different ways...
  15. H

    VM crash with memory hotplug

    We're having problems with all newer pve-qemu-kvm versions, every version newer than 2.5.19 is causing a unpredictable crash of our VM's. I've setup some tests and reproduce details, can you please check your configuration, with this test you can crash your VM in a few minutes. My test VM...
  16. O

    CPU/RAM hot plugging with KVM

    Hello, I'm experimenting CPU and RAM hot plugging with KVM. I can add or remove RAM from a running VM. It works great! I have read that reducing RAM is not supposed to work, but all worked at the first try. Maybe I read outdated articles? (tested with proxmox 4.3, ubuntu 16.04 guest) I can...
  17. M

    memory hotplug problem with net vmbr

    Hello, we have just successfully installed proxmox ve and I have found one problem. I am not able to start virtual instance if the vm has memory hotplug enabled, memory is set higher that 32GB and net interface is bridged (via vmbr). If I disable net bridge and I will use NAT that I can start...


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