-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Saturday 2006-04-29 at 13:19 +0200, Hylton Conacher (ZR1HPC) wrote:
understand an SMTP server must send its load to another SMTP server. To clarify let us assume there are only 3 SMTP servers in the world ie my local one, my ISP's one, the destination one.
Me-- |A|----------Broken link--------------|B| \ / \---------Link OK-------|C|--------/
[A] Mozilla ----- local----\---------------------- Destination [B] \ postfix \ / SMTP \ \ [C] / -------------------ISP ---------/ SMTP Those are the possibilities.
Let us assume that A cannot see the destination B. It determines that the alternate path to B is via C.
It's rather that you tell it to do it that way; it doesn't do it automatically. The route is decided looking at its configuration and the answers from the DNS.
The destination (B) does not need to authenticate the messages it receives
It doesn't because it is the SMTP server responsible to receive email for the domain in the "To" field. Ie, it is not a relay, but the final destination.
however C does. So while my local SMTP server is connected and sending mail to C, C does authentication and sees that the FROM header in some of the emails is not the same as the email address as the person logged onto the ISP. C therefore drops those messages into the forever ether. The messages whose FROM header is the same as the person dialed in are relayed to the destination server (B).
Well, that's because the person administering that crappy server has decided to do it that way, IMO. I know it happens. It should, however, never "drop" mail, but "reject" mail. That's very irresponsible on their part.
Can the above happen to a local SMTP server (A) as it has been happening to Me when I sent email directly from my Mozilla Mail to C. If the FROM header in some of the emails is not the same as the email address as the person logged onto the ISP. C therefore drops those messages into the forever ether. The messages whose FROM header is the same as the person dialed in are relayed to the destination server (B).
I prefer to send through (A) because that way I see the logs, and reading them I know what is happening. If I get a rejection, I know it, not a box popping up from mozilla telling me of a error in transmission. I get more control. However, you can tell (A) to send directly to (B). That's what I normally do. It works with SuSE lists, but it doesn't with some other recipients: they check that (A) is on a dynamic address and refuse talking. - -- Cheers, Carlos Robinson -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFEVJFitTMYHG2NR9URAt6aAJ0SL0h0y0upbe4WxyqrCHjun8ZtsQCeNrNw 8wo+FURX01WhlDlDX33E+pI= =ZSFF -----END PGP SIGNATURE-----