You  need to reinstall the host after having  enabled the nested feature and obviously reboot the host so as it will boot with the new kernel feature. Le 26 févr. 2021 19:57, miguel.garcia(a)toshibagcs.com a écrit : Hi all, We are trying to run virtual box in a vm that is running over ovirt platform. I had followed the instruction to enable nested virtualization on host as described in this document https://ostechnix.com/how-to-enable-nested-virtualization-in-kvm-in-linux/ However I was not able to enable nested virtualization to the vm since nothing is listed from virsh console. Also tryed to edit vm configuration lookig up for "cpu mode" or "copy cpu configuration as host" Also from oVirt admin portal I had enabled host for nested virtualization through Compute > Host > selected Host > edit > Kernel Nested virtualization checked. But the host still returns: $ cat /sys/module/kvm_intel/parameters/nested N _______________________________________________ Users mailing list -- users(a)ovirt.org To unsubscribe send an email to users-leave(a)ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/U7IPOFY3747...

There are two main parts to nested KVM. 1st the host must have it enabled, so put host in maintenance mode through engine UI, set boot option to add it, go to UI host 'installation'->reinstall to pick up the changes and reboot, or is it reboot and then reinstall, I forget. [image: nested-1.JPG] 2nd part is enabling the VM in the VM edit dialog by setting 'Host' CPU option Pass-Through for the VM. [image: nested-2.JPG] On Mon, Mar 1, 2021 at 4:19 PM <miguel.garcia(a)toshibagcs.com&gt; wrote: