import socket


def dns_lookup_forward(hostname):
    """Forward DNS lookup.

    :param hostname: hostname
    :type hostname: `str`
    :return: list of IPs as strings
    :rtype: `list`
    :raises ValueError,IOError:
      - ValueError - on empty hostname
      - IOError - on any IP address resolution errors
    """
    if not hostname:
        raise ValueError('Empty hostname provided.')
    try:
        _, _, ips = socket.gethostbyname_ex(hostname)
    except (socket.gaierror, socket.herror) as e:
        raise IOError(str(e))
    return ips