On 21/07/16 13:38, Tobias Gablunsky wrote: > Just to answer my own question: No, underscores are not allowed in hostnames as of RFC 1123 (see also http://stackoverflow.com/questions/2180465/can-domain-name-subdomains-have-an-underscore-in-it/2183140#2183140). > Wasn't that superseded to allow SRV records etc? S