[Mailman-Users] "sender domain must resolve" errors

[Chuq Von Rospach]

On 5/16/01 9:30 AM, "Bob Puff at NLE" <bob at nleaudio.com> wrote:
> I've noticed that I'm seeing a lot of "Sender domain must resolve" messages
> in my Postfix logs, most of which are from messages sent thru Mailman.  I know
> this isn't specifically a mailman issue, as the errors are coming from the
> other SMTP servers, but perhaps someone here can help shed light on this.

It's a disturbance in the DNS. It's possible your DNS server was temporarily
flakey, but when I see that, it's more normally a networking issue of some
sort. And it's not necessarily the network between them (trying to look you
up) and your DNS (trying to answer) -- I've seen it when a router between a
chunk of net and the root DNS servers goes flakey or overloads, so they
can't resolve you out of the root.