Re: smtp daemons
Hi
Many thanks for this information.
Matthew
On Fri, Jun 29, 2001 at 08:23:56AM +0200, Michael Wood wrote:
> Hi
>
> On Thu, Jun 28, 2001 at 10:00:27PM +0100, Matthew Sackman wrote:
> > Hi Guys,
> >
> > When you send an email and it goes to the smtp server, that
> > server then tries to connect to the mail exchange for the
> > domain which the email is going to.
> >
> > Will it connect to this mail exchange from port 25, or will it
> > open another unpriveledged port? I'm just wondering whether I
> > can set a firewall option to only allow connections to the
> > smtp server if it comes from port 25.
>
> SMTP clients (including other SMTP servers sending your SMTP
> server mail) use an unpriveleged port as the source port. (I
> suppose some clients could use port 25, but I've never seen
> that.)
>
> i.e. if you add a rule to allow only tcp src port 25 to tcp dst
> port 25, you will not get mail.
>
> --
> Michael Wood | Tel: +27 21 762 0276 | http://www.kingsley.co.za/
> wood@kingsley.co.za | Fax: +27 21 761 9930 | Kingsley Technologies
>
>
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>
--
Matthew Sackman
Nottingham,
ENGLAND
Using Debian/GNU Linux
Enjoying computing
It said 'Required Windows XP or better.'
So I installed Linux.
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