[Cialug] Email server

[Nicolai]

On Mon, May 01, 2017 at 12:53:59PM -0500, khamil8686 at gmail.com wrote:

> One thing I wondered, if I set up an authoritative nameserver on port 53
> using my domain name, point dns towards there, and put reverse lookup
> for my home mail server, would emails be rejected?

> Purely an academic example that I was curious about.

Well, your authoritative nameserver wouldn't be responsible for
answering reverse DNS queries for your IP address; that's your ISP's
job.  In other words, nobody would ask your NS for the PTR record of
e.g. 53.2.0.192.in-addr.arpa.  All those queries would go to your ISP's
nameservers.

dig +short ns cialug.org.
dig +short cialug.org. # currently 67.224.64.36
dig +short ns 64.224.67.in-addr.arpa.

Nobody asks the cialug.org nameservers questions about 67.224.64.36.

To get a specific PTR record for your IP address, you'd have to ask
your VPS/colo provider.

Nicolai