Mailinglist Archive: opensuse (3337 mails)

< Previous Next >
Re: [SLE] mail sending and Postfix was OT: Posting from another unsubscribed address for a subscriber?
  • From: "Carlos E. R." <robin.listas@xxxxxxxxxxxxxx>
  • Date: Mon, 24 Apr 2006 00:40:27 +0200 (CEST)
  • Message-id: <Pine.LNX.4.61.0604240019340.18989@xxxxxxxxxxxxxxxx>
Hash: SHA1

The Thursday 2006-04-20 at 13:08 +0200, Hylton Conacher (ZR1HPC) wrote:

> THANKS Carlos, my reply/understanding is in-line.

As it should always be.

> So in essence, provided an individual/company uses the ISP of their domain
> holder(ISP-1), they can use the ISP SMTP servers. If an individual/company
> wants to obtain a domain at another ISP(ISP-2) and dial into ISP-1 to send
> mail from the IAP2 domain, it is not 'allowed' to cut down on spam?

It depends on what rules the smtp server you want to use as relay server
imposses on you. They can allow you, or not. Their choice.

> There is something I am missing however :(
> Something about the authentication :(
> What hapens to folk who maintain their own SMTP servers(Postfix/Sendmail etc)?
> Are they still restricted in sending mail from another another domain(ISP-2)
> via a different ISP(ISP-1)?

If your provider is a good one they will not impede you from using their
smtp as a relay server for all your email regardless of the from address
you use.

> Let me illustrate with an example on how I understand the SMTP process:
> 1. Assume that I had a two domains registered, each with a different
> ISP.
> ISP-1
> ISP-2
> 2. I have a single Postfix SMTP server for both domains, but I cannot
> afford to keep it online 24/7 and so I have a dialup account with
> ISP-1.
> 3. On first dialup to ISP-1 my SMTP server authenticates and retrieves
> its dynamic IP from ISP-1.

Nonononono. You get your IP much earlier that that, via ppp negotiation
when the modem connects.

> It first sends the outgoing email from
> both domains to the next closest SMTP server(ISP-1's SMTP server) and
> then receives email from POP mail stores at each domain. My SMTP
> server then disconects itself from ISP-1.

It sends email to the server you have told it to send to. Distance or
ownership has nothing to do. Nor has the smtp server got to connect or
disconect after or before you receive mail from the pop server(s).

> 4. The mail received by ISP-1's SMTP server is marked as certified as
> ISP-1 was able to confirm that the sender was someone who they knew
> and who had dialed into the ISP-1 network. The message details from
> the message sender do not matter as they came from an authenticated
> source. If there is a problem with one of the messages sent then
> ISP-1 will be able to identify me as the sender and I could face
> legal action.

I'm sorry, but I do not understand a word of what you are saying. Please,
study the subject in manuals and howtos available in the distro, then
explain again.

I already explained what you needed to know, but what you say doesn't make
any sense. Or I'm thick headed today, sorry.

Let me try again... when you send email by any method using any relay
server you hired, because it belongs to your isp, that email can be traced
back to you regardless of your from address, and regardless of the method
you used to authenticate yourself to the isp or smtp server - provided
everything is correctly configured at their end.

This relay server will normally send all that email direct to the
destination address, no intermediaries. The destination server can not do
authentification, because the email is for him: he can not reject it,
unless he thinks it is spam or virus or such.

- --
Carlos Robinson
Version: GnuPG v1.4.0 (GNU/Linux)
Comment: Made with pgp4pine 1.76


< Previous Next >