DCCM mail_host grabs smart_host setting?

Vernon Schryver vjs@calcite.rhyolite.com
Thu May 1 14:03:51 UTC 2003

> From: "Sven" <sven@dmv.com>

> ...
> mail from someuser@somedomain.com coming from smtp.somedomain.com for
> example should have mail_host of somedomain.com. If the mail doesn't get
> rejected, it then proceeds on to the smart_host --> smarthost.mydomain.com
> INSTEAD I see the following in the messages in the log directory
> mail from someuser@somedomain.com coming from smtp.somedomain.com ends up
> with mail_host of smarthost.mydomain.com
> I don't know if this is due to the way sendmail and dccm interact i.e. does
> sendmail perform the smart_host substitution prior to dccm invocation?
> ...

I think sendmail passes the SMTP envelope Mail_From value to a milter
filter such as dccm unchanged and unchecked.  Judging from a test or
two just now, that seems to be true.
Dccm then does a simplistic fiddling on the Mail_From value to pick out
a value to call the mail_host.

In other words, the only ways I think of for you to see those values
involve the envelope Mail_From value cnotaining
That might happen if the original sender has configure an MUA to
use that source address.  It might also happen if this instance of
dccm+sendmail are not first, but the message has already been passed
through an MX secondary or other MTA that replaced somedomain.com
with smarthost.mydomain.com.

Vernon Schryver    vjs@rhyolite.com

More information about the DCC mailing list

Contact vjs@rhyolite.com by mail or use the form.