During a recent customer visit we had a testing environment available on where some VM’s couldn’t be powered on/vMotionned to some of the ESXi Hosts. The error message:
An error was received from the ESX host while powering on VM xxxxx.
Failed to start the virtual machine.
Module DevicePowerOn power on failed.
Unable to create virtual SCSI device for scsi1:0, ‘/vmfs/volumes/39dfa56f-83350d20/xxxxxx/xxxxxx.vmdk’
Failed to attach filter ‘pxdacf_filter’ to scsi1:0: Not found (195887107).
The error message is similar to the one which VMware is describing in this KB article around vShield Endpoint: The virtual machine power-on operation fails with this error when a virtual machine that was earlier protected by vShield Endpoint is either moved or copied to a host that is not protected by the vShield Endpoint security solution.
However this customer wasn’t using vShield in this test environment and Google didn’t got any hits on the “pxdacf_filter”. Troubleshooting eventually pointed out that some of the ESXi Hosts had Proximal Data AutoCache installed and VM’s that are accelerated by Proximal contain the following lines in their .vmx file:
scsix:x.filters = “pxdacf_filter”
Which obviously caused the VM to be unable to power-on on an ESXi Host without Proximal Data AutoCache installed.