> On Dec 1, 2017, at 1:19 PM, Chris Green <c...@isbd.net> wrote:
>
> I have run postfix for a number of years on my home (xubuntu) server
> machine with my router firewall limiting connections on port 25 to
> just the range of IP addresses which are my domain hosting company's
> SMTP servers.
Is this outbound or inbound? If inbound, why do you only expect
SMTP connections from the hosting provider? If outbound, why port
25 and not 587?
> Is there much risk if I open up port 25 to any IP address? I have it
> this way at the moment and there are only a few (as in ten or a dozen)
> rogue connections per day so it doesn't seem as if port 25 is really
> very popular for hackers and such.
Can you explain these "rogue" connections? If inbound, that's expected,
if outbound, what on your network would be making unexpected outbound
connections and why?
--
Viktor.
