def fqdn_split(fqdn):
    """split a fully qualified domain and return the host name and dns domain,
    when no domain has been specified an empty string will be returned as 
    dns domain"""
    split_host = fqdn.split('.')
    if len(split_host) == 1:
        host_name = split_host[0]
        dns_domain = ''
    else:
        host_name = split_host.pop(0)
        dns_domain = '.'.join(split_host)
    return host_name, dns_domain