[dns-operations] about the underline in hostname

[Jim Reid]

On 29 May 2014, at 18:20, Bob Harold <rharolde at umich.edu> wrote:

> If I (reluctantly) accept that DNS names that are not hostnames can have
> underscores in them, why does BIND not have an option to allow that, while
> still rejecting invalid hostnames?  Or have I missed something?

I think you have missed something.

BIND does allow domain names with underscores in them. In fact SRV records use underscores so that names with those _service._proto labels can't be confused with hostnames.

BIND9 has a check-names hook to ignore, warn and fail RRs that should comply with hostname syntax but don't. It's been there for years.