NVDCF fails in the official Deepstream 5.1 docker image

Please provide complete information as applicable to your setup.

• Hardware Platform (Jetson / GPU) Jetson
• DeepStream Version 5.1
• JetPack Version (valid for Jetson only) 4.5.1
• TensorRT Version 7.1.3
• NVIDIA GPU Driver Version (valid for GPU only)
• Issue Type( questions, new requirements, bugs)
• How to reproduce the issue ? (This is for bugs. Including which sample app is using, the configuration files content, the command line used and other details for reproducing)
• Requirement details( This is for new requirement. Including the module name-for which plugin or for which sample application, the function description)

Probably due to missing VPI lib I am getting

 nvtracker gstnvtracker.cpp:246:gst_nv_tracker_start: gstnvtracker: Failed to initialize trackerIface
root@c1f6412febb8:/opt/nvidia/deepstream/deepstream/lib# ld libnvds_nvdcf.so
ld: warning: libnvvpi.so.1, needed by libnvds_nvdcf.so, not found (try using -rpath or -rpath-link)
ld: warning: cannot find entry symbol _start; not setting start address
libnvds_nvdcf.so: undefined reference to `vpiCreateExtractColorNameFeatures'
libnvds_nvdcf.so: undefined reference to `vpiSubmitExtractHOGFeatures'
libnvds_nvdcf.so: undefined reference to `vpiImageCreateCUDAMemWrapper'
libnvds_nvdcf.so: undefined reference to `vpiStatusGetName'
libnvds_nvdcf.so: undefined reference to `vpiImageDestroy'
libnvds_nvdcf.so: undefined reference to `vpiStreamSync'
libnvds_nvdcf.so: undefined reference to `vpiGetLastStatusMessage'
libnvds_nvdcf.so: undefined reference to `vpiStreamCreate'
libnvds_nvdcf.so: undefined reference to `vpiCreateExtractHOGFeaturesBatch'
libnvds_nvdcf.so: undefined reference to `vpiSubmitExtractColorNameFeatures'
libnvds_nvdcf.so: undefined reference to `vpiStreamDestroy'

Manually installing it inside a docker container fails with broken dependencies

root@c1f6412febb8:/tmp# apt install ./vpi-lib-1.0.15-aarch64-l4t.deb
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'libnvvpi1' instead of './vpi-lib-1.0.15-aarch64-l4t.deb'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libnvvpi1 : Depends: cuda-cufft-10-5 but it is not installable or
                      libcufft-10-5 but it is not installable or
                      cuda-cufft-10-4 but it is not installable or
                      libcufft-10-4 but it is not installable or
                      cuda-cufft-10-3 but it is not installable or
                      libcufft-10-3 but it is not installable or
                      cuda-cufft-10-2 but it is not installable or
                      libcufft-10-2 but it is not installable or
                      cuda-cufft-10-1 but it is not installable or
                      libcufft-10-1 but it is not installable or
                      cuda-cufft-10-0 but it is not installable or
                      libcufft-10-0 but it is not installable or
                      cuda-cufft-11-5 but it is not installable or
                      libcufft-11-5 but it is not installable or
                      cuda-cufft-11-4 but it is not installable or
                      libcufft-11-4 but it is not installable or
                      cuda-cufft-11-3 but it is not installable or
                      libcufft-11-3 but it is not installable or
                      cuda-cufft-11-2 but it is not installable or
                      libcufft-11-2 but it is not installable or
                      cuda-cufft-11-1 but it is not installable or
                      libcufft-11-1 but it is not installable or
                      cuda-cufft-11-0 but it is not installable or
                      libcufft-11-0 but it is not installable
             Depends: cuda-cudart-10-5 but it is not installable or
                      cuda-cudart-10-4 but it is not installable or
                      cuda-cudart-10-3 but it is not installable or
                      cuda-cudart-10-2 but it is not installable or
                      cuda-cudart-10-1 but it is not installable or
                      cuda-cudart-10-0 but it is not installable or
                      cuda-cudart-11-5 but it is not installable or
                      cuda-cudart-11-4 but it is not installable or
                      cuda-cudart-11-3 but it is not installable or
                      cuda-cudart-11-2 but it is not installable or
                      cuda-cudart-11-1 but it is not installable or
                      cuda-cudart-11-0 but it is not installable
E: Unable to correct problems, you have held broken packages.

libnvvpi.so.1 is part of deepstream SDK. Please check whether your deepstream SDK is installed correctly.

Deepstream (deepstream-5.1 deb package) is not installed on the host of OS. What would be the point of using the images then if it had to be installed twice?

You don’t need to install twice. Just upgrade JetPack with sdkmanager for your host.