Mastering Proxmox - Third Edition

Hotplugging vCPUs

To add a virtual CPU or vCPU, go to the Datacenter | Node | VM | Hardware menu. Then, select Processors and click on Edit to open the dialog box. Simply type in the number of cores or use the up and down option in the text to choose the desired number of cores or vCPUs. Click on OK to accept the changes. We can also add a new CPU from this dialog box. We can also add vCPUs by running the following command from the Proxmox node CLI:

# qm set <vm_id> -vcpus 2

Since our example VM already has one CPU, the previous command will add an additional CPU, making it a total of two CPUs for the VM.