Inside boot2docker (boot2docker ssh) / docker-machine (docker-machine ssh default) , open or create the file /var/lib/boot2docker/profile and add the following line:
EXTRA_ARGS="--dns 192.168.1.145"
Also works for:
EXTRA_ARGS="--insecure-registry myinternaldocker"
After the change you need to restart the docker daemon:
sudo /etc/init.d/docker restart
Or leave boot2docker / docker-machine and restart the entire virtual machine:
boot2docker restart
# for docker machine
docker-machine restart default