Today I learned about nsenter: a small tool that allows you to run stuff from the host inside of a container.
Finally, I don't have to install tools inside the container any more.
One example:
https://contractdesign.github.io/docker/2021/06/10/nsenter.html
Running a Command from a Host in a Docker Container (nsenter)
I was trying to monitor traffic between containers in an internal Docker network and started down the path of writing Python with the Docker SDK to query /proc but thought there had to be an easier way. There are many great monitoring tools already written that I should be able to use. My problem was that they aren’t installed in the containers (and I don’t want to rebuild the containers), but they are already on my host computer. Is there a way to use them?

