Increment image tag

As per my previous question I would now like to increment the tag of the image I push to the local registry.
Using the docker plugin, I have set auto_tag: true but it does not increment the tag.
What am I doing wrong?

Using the docker plugin, I have set auto_tag: true but it does not increment the tag. What am I doing wrong?

auto-tag creates docker images using the git tag, not an auto-incremented number, which means this field is not intended for your use case.

I would now like to increment the tag of the image I push to the local registry.

some people use the build number as the tag. See an example I provided here: http://discuss.harness.io/t/using-tags-as-a-build-arg-in-the-docker-plugin/6505/7?u=bradrydzewski

Thanks, I like the idea of using the Drone build number.