Runner Registeration Command for Docker using host's docker socket

gitlab-runner register  --url http://localhost:8000 \
                        --token glrt-qL_FTjkAGqy7SHcYYStx \
                        --executor docker \
                        --name "Docker Runner" \
                        --docker-image "python:3.10-alpine" \
                        --docker-volumes "/var/run/docker.sock:/var/run/docker.sock" \
                        --docker-network-mode "host"

GitLab Networking

How GitLab runner use /var/run/docker.sock for container creation