Selfhosted Runners kubernetes, docker sock problem

Hi, We have an issue with running the self hosted agents in our kubernetes cluster.

It is set up according to the documentation, and it accepts jobs.
The issue occurs when we want to build in the pod.

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

How can i change the config to run this. Docker in docker? or remote docker?

The latter I have tested, but with no success.
Does anyone have a guide, or some good tips to share?