docker-machine create --driver virtualbox mytest

docker-machine ip mytest
192.168.99.103

docker run -p 3306:3306 --name mysql -d
  -v /opt/mysql/data:/var/lib/mysql
  -e 'DB_USER=sampleuser' -e 'DB_PASS=samplepass' -e 'DB_NAME=sampledb' -e 'DB_REMOTE_ROOT_NAME=root' -e 'DB_REMOTE_ROOT_PASS=samplerootpass'
  sameersbn/mysql:latest

▶ mysql -u root -p -h 192.168.99.103
Enter password:
ERROR 1045 (28000): Access denied for user 'root'@'192.168.99.1' (using password: YES)

▶ ifconfig | grep "192"
    inet 192.168.99.1 netmask 0xffffff00 broadcast 192.168.99.255