[CentOS] sendmail mail relay backscatter issue.

Thu Feb 4 15:05:00 UTC 2010
Simon Billis <simon at houxou.com>

Hi,
> >>running
> >> make -C /etc/mail but this has no effect on the sendmail.cf file. My
> 
> Does it not give output? Have you tried adding -d?
I get an updated sendmail.cf file but the only diff is the header telling me
when it was complied.

Adding -d give the following (I've removed the non relevant lines):

  No implicit rule found for `sendmail.mc'.
     Finished prerequisites of target file `sendmail.mc'.
    No need to remake target `sendmail.mc'.
   Finished prerequisites of target file `sendmail.cf'.
   Prerequisite `sendmail.mc' is newer than target `sendmail.cf'.
  Must remake target `sendmail.cf'.
make: Entering directory `/etc/mail'
Putting child 0x05474670 (sendmail.cf) PID 10927 on the chain.
Live child 0x05474670 (sendmail.cf) PID 10927 
Reaping winning child 0x05474670 PID 10927 
Removing child 0x05474670 PID 10927 from chain.
  Successfully remade target file `sendmail.cf'.


> > Another would be to use MimeDefang as the framework instead of
> > mailscanner.  It has an option to check recipient addresses via smtp
> to
> > the delivery servers before accepting.  You may have to write a
> snippet
> > of perl to get that right for multiple domains (that's a feature...).
> > This is less efficient but works in real time against the addresses
> that
> > will be accepted for delivery.
> 
> I would question how "real time" that would be for every email for 6k+
> domains. If a few have a large client base, or are expecting responses
> from a mass emailing, it might start to take a *while*, unless you've
> got
> pretty heavy duty equipment and networking.

I agree - I think that the overhead that perl would impose is too high for
this application.

Thanks

S.