Change VM settings

[steve1977]

I have a VM running, set up with i440fx and USB 2.0 (EHCI). I understand that Q35 and USB 3.0 (qemu XHCI) is recommended as most modern.

 

Any suggestion how to make such update for an existing VM?

 

Thanks!

[ghost82]

Fastest way is to create a new vm and point it to the actual vdisk and add the same devices.

This is because i440fx and q35 have different layouts, i440fx attaches all on bus 0, q35 has bus 0, defined by the pcie-root, with different pcie-root-ports attached to it for other buses.

Changing the machine type in the gui will not change the layout so you will receive error, most probably the first one that a pcie-root is not defined.

One can modify the xml manually, but it will be the same as creating a new vm, in this last case in less time.