Apt update error for tensorrt package

Hi,
I have followed the installation procedure of Tensorrt 8 on CUDA-11.4 as described in [1]. However, as you can see below, the apt update command returns error about untrusted source.

$ sudo dpkg -i ~/Downloads/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212_1-1_amd64.deb 
Selecting previously unselected package nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212.
(Reading database ... 315483 files and directories currently installed.)
Preparing to unpack .../nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212_1-1_amd64.deb ...
Unpacking nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212 (1-1) ...
Setting up nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212 (1-1) ...
$ sudo apt-key add /var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212/*.pub
OK
$ sudo apt-get update
Get:1 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  InRelease
Ign:1 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  InRelease
Get:2 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  Release [569 B]
Get:2 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  Release [569 B]
Get:3 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  Release.gpg [801 B]                                                                     
Get:3 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  Release.gpg [801 B]                                                                     
Get:4 http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1604/x86_64  InRelease [1,581 B]                                                                 
Get:5 https://download.docker.com/linux/ubuntu focal InRelease [57.7 kB]                                                                                             
Get:6 file:/var/nv-tensorrt-repo-ubuntu2004-cuda11.6-trt8.4.0.6-ea-20220212  Packages [4,635 B]                                                                      
Get:7 https://linux.teamviewer.com/deb stable InRelease [11.9 kB]                                                                                                    
Hit:8 http://deb.anydesk.com all InRelease                                                                                                                           
Err:4 http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1604/x86_64  InRelease                                                                           
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A4B469963BF863CC

Any idea how to fix that?

Hi,
Please refer to the installation steps from the below link if in case you are missing on anything

Also, we suggest you to use TRT NGC containers to avoid any system dependency related issues.

Thanks!