On 23 January 2018 at 16:12, Andrew Sullivan <a...@anvilwalrusden.com> wrote: > On Tue, Jan 23, 2018 at 10:50:24AM -0500, Kris Deugau wrote: >> >> There is no One True Standard, and even within the more common conventions >> there are quite a few variations. > > And even if people came up with a standard, the operator could lie. > After all, it's just DNS. There are no DNS Police to come and tell > you that you are using names wrong, or revoke your Internet license if > you do so.
OK points taken thanks. Corollary: an outgoing mailserver needs an rDNS that *indicates* a static ip - regardless of whether the ip is actually static or dynamic. Because plenty of real-world mailservers do block or severely limit mail from 'dynamic IPs' (e.g. gmail) but they can base this only on a 'best guess'.
