Intel vaapi error: can't connect to X server

I am using an EC2 with Ubuntu 18.04, CPU Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz, and a Nvidia Tesla T4. It seems vainfo reports a problematic setup:

error: can't connect to X server!
libva info: VA-API version 1.1.0
libva info: va_getDriverName() returns -1
libva error: va_getDriverName() failed with unknown libva error,driver_name=(null)
vaInitialize failed with error code -1 (unknown libva error),exit

My goal is to use vaapi accelerated HW decoding with gstreamer in Python.

lspci | grep VGA returns:

00:01.3 Non-VGA unclassified device: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 08)
00:03.0 VGA compatible controller: Amazon.com, Inc. Device 1111

Note:

I installed on the EC2 the Nvidia drivers (not sure if they could interfere with Intel's graphic card)
I also installed OpenVINO
I was following this guide http://lifestyletransfer.com/how-to-install-gstreamer-vaapi-plugins-on-ubuntu/ for the setup and I got stuck at the point when I run vaapi

How can I fix this?

Solution

The CPU does not have Intel integrated graphic card.