On Wed, 01 Jan 2003, SuSEnixER just had to get this off his chest:

* Theo v. Werkhoven [01-01-03 19:14]:

...

On Wed, 01 Jan 2003, Linux just had to get this off his chest:

...

Hi guys... I'm getting the following error on my email server...

MAIL FORM user@domain.com and then the SMTP server [server-ip] said 451.4.1.8 Domain of sender address user@domain.com does not resolve.

Any clue of what, it happening...

Either the DNS that's responsible for that domain had a problem, or you try to use a non-existing domain. It's impossible to tell if you munge the info.

Or perhaps the message envelope_from does not match the 'From: ' address in the header. ??

The From: address is not /in/ the header, it's in the body.. SMTP doesn't do anything with From:, Reply-To: etc. Theo -- Theo v. Werkhoven Registered Linux user# 99872 http://counter.li.org ICBM 52 13 27N , 4 29 45E. SuSE 8.0 x86 Kernel k_Athlon 2.4.19-4GB See headers for PGP/GPG info.

On Thu, 02 Jan 2003, Jerry just had to get this off his chest:

"Theo v. Werkhoven" wrote:

...

The From: address is not /in/ the header, it's in the body.. SMTP doesn't do anything with From:, Reply-To: etc.

The From:, subject: and To: are most definitely in the message header.

Yes but *not* in the SMTP header (envelope) however, which is what this was all about.

Here is a URL describint the mbox format: http://www.qmail.org/qmail-manual-html/man5/mbox.html In brief general terms. Every line in an email message from the beginning of the message to the first blank like is in the header. SMTP does not process the From:, and the From: line may even be added by the MTA (eg. sendmail).

Which is what I ment. When you look at a SMTP conversation you'll notice that From: etc won't come up until the data portion. Because the OP was describing a SMTP convers I pointed out that From: has nothing to do with his problem of the complaining DNS.

If you want to know more about SMTP: http://www.ietf.org/rfc/rfc0821.txt It's quite dry.

As it should be for RFCs. But I understand SMTP well enough for my purposes, thank you. Theo -- Theo v. Werkhoven Registered Linux user# 99872 http://counter.li.org ICBM 52 13 27N , 4 29 45E. SuSE 8.0 x86 Kernel k_Athlon 2.4.19-4GB See headers for PGP/GPG info.