[nycbug-talk] Dynamic DNS MX Records

[Charles Sprickman]

On Tue, 17 Jan 2006, Jonathan wrote:

> That just reminded me-
>
> Many DSL/Cable providers block all traffic on port 25, unless it's being 
> routed to their SMTP servers .
> They tend to consider any machine sending mail on port25 to be compromised 
> and sending virus/spam , as they far more often than not are.
>
> I'd check to make sure they have port 25 open.

And check that it's open in BOTH directions if you're running a mail 
server.  I know at one point not only did VZ block outbound 25 to anything 
but their own server, but they also only allowed @verizon.net From: 
addresses...  Brilliant.  I think that went away, but you have to wonder 
who dreams things like that up and who approves them for the final rollout 
to all their subs.

C