Docker-images: failed to dial gRPC: unable to upgrade to h2c, received 502 context canceled

[deepanshurana]

when i try to run the buildDockerImage.sh using:
./buildDockerImage.sh -v 12.2.0.1 -e
i get the following error:

Ignored MD5 sum, 'md5sum' command not available.
==========================
DOCKER info:
Error response from daemon: Bad response from Docker engine
==========================
Building image 'oracle/database:12.2.0.1-ee' ...
ERRO[0000] failed to dial gRPC: unable to upgrade to h2c, received 502 context canceled

ERROR: Oracle Database Docker Image was NOT successfully created.
ERROR: Check the output and correct any reported problems with the docker build operation.

Can you please help me in it?
I have a database zip file already downloaded in specified version folder.

[gvenzl]

That is a Docker internal error that you are getting, nothing to do with the build itself.
The issue is referenced over here, maybe that helps: https://github.com/docker-library/docker/issues/71

[prahamurali]

You must wait for some minutes before the docker starts