[dns-operations] Zone cut on _tcp.example.ca

Jacques Latour jacques.latour at cira.ca
Tue Feb 9 15:10:15 UTC 2016


Hi,

One of our d-zone (secondary dns service) customers wants to a zone that looks like this:  _tcp.example.ca

My initial gut feeling was "no", LDH, not a valid label/domain name, but Roy said maybe, RFC2181 section 11. "The DNS itself places only one restriction on the particular labels  that can be used to identify resource records.  That one restriction relates to the length of the label and the full name.  The length of  any one label is limited to between 1 and 63 octets.".

_tcp.example.ca.  86400   IN      SOA     ns01.example.ca. postmaster.example.ca. 6224 3600 60 1209600 600
_tcp.example.ca.  86400   IN      NS       ns01.example.ca.

It looks as though bind accepts this as a valid zone, though I am not 100% convinced that it is.
But then you could end up with RR like this;  _http._tcp.jack._tcp.cira.ca

Any feedback appreciated,

Jack, Evan

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.dns-oarc.net/pipermail/dns-operations/attachments/20160209/34484e87/attachment.html>


More information about the dns-operations mailing list