#add this function to your .bash_profile

update-docker-hosts(){
        # clear existing *.docker.local entries from /etc/hosts
        sudo sed -i '' '/\.docker.local$/d' /etc/hosts

        # iterate over each machine
        docker-machine ls | tail -n +2 | awk '{print $1}' \
        | while read -r MACHINE; do
                MACHINE_IP="$(docker-machine ip ${MACHINE} 2>/dev/null)"
                [[ -n $MACHINE_IP ]] && sudo /bin/bash -c "echo \"${MACHINE_IP} ${MACHINE}.docker.local\" >> /etc/hosts"
        done
}