Repository is not signed in docker build

Since Docker API v1.25+ ( released: Nov 18, 2019 )

Running the command below fixed the problem for me:

docker system prune --force

The --force flag stands for noninteractive prune.

Additionally, you may want to give a try to the prune volume commands:

docker volume prune --force

Apparently my root partition was full (maybe I've tried too many times to download packages through apt), and running sudo apt clean solved the issue


In addition, the following commands should help clean up space:

docker system df # which can show disk usage and size of 'Build Cache'
docker image prune # add -f or --force to not prompt for confirmation
docker container prune # add -f or --force to not prompt for confirmation

Tags:

Docker

Ubuntu

Apt