good address will not resolve in freebsd (_ in host names)

[Matthew George]

On Tue, 7 Oct 2003, Andi Hechtbauer wrote:

> Just FYI,
>
> Restrictions on hostname character sets seem obsoleted by this:
>
> >From RFC2181, Section 11
>
>    [...] any binary string whatever can be used as the label of any
>    resource record.  Similarly, any binary string can serve as the
>    value of any record that includes a domain name as some or all of
>    its value (SOA, NS, MX, PTR, CNAME, and any others that may be
>    added).  Implementations of the DNS protocols must not place any
>    restrictions on the labels that can be used.  In particular, DNS
>    servers must not refuse to serve a zone because it contains labels
>    that might not be acceptable to some DNS client programs. [...]
>
> Regards,
> Andi
>
>

underscores are part of the SRV RR spec for services and protocols ...

from RFC 2782:

The format of the SRV RR

   Here is the format of the SRV RR, whose DNS type code is 33:

        _Service._Proto.Name TTL Class SRV Priority Weight Port Target

        (There is an example near the end of this document.)

-- 
Matthew George
SecureWorks Technical Operations