Dear all, I am suffering a problem in my OpenStack servers. I have a 3 server configuration: - controller + compute - 2 x compute nodes The controller node has an Nvidia L4 configured in vGPU mode. One of the compute nodes has another Nvidia L4 in vGPU mode. Both servers are running fine, and I can deploy instances with vGPU capabilities. The problem comes with my 2nd compute node; that node has a Nvidia RTX4000 that can only work in passthrough mode. , I am pretty sure that in past times I managed to deploy this compute node with an Nvidia RTX 4000 in passthrough mode as a compute node of another OpenStack server configuration, but nowadays I am not able to use that GPU in passthrough mode and I don't know why: - I have configured IOMMU in compute node - I have configured nova.conf with pci alias and whitelist in compute node - I have configured nova.conf with pci alias and enabled filters in controller node - I have created a flavor and set up pci_passthrough:rtx:1 to it's configuration As far as I know, those are the steps to configure a GPU passthrough in a compute node in a Openstack multi-node configuration... But when I try to deploy a new instance I am always getting a "PCI alias rtx is not defined (HTTP 400)" error. Any ideas about what could be the problem? Is there any incompatibility with vGPU and passthrough working modes? Thanks in advance. Felipe -- [image: Vicomtech] <https://www.vicomtech.org> Industry Division Juan Felipe Mogollón Rodríguez Senior Researcher Digital Media and Communications fmogollon@vicomtech.org +(34) 943 30 92 30 The information contained in this electronic message is intended only for the personal and confidential use of the recipients. If you have received this e-mail by mistake, please, notify us and delete it. Avoid printing this message if it is not strictly necessary.