Re: first stab at simple mailer

[Bill Hacker <wbh@xxxxxxxxxxxxx>]

Simon 'corecode' Schubert wrote:
> Rahul Siddharthan wrote:
> > > >     But you still need to efficiently queue the mail for 
> > > > forwarding.  You
> > > >     can't just make separate connections to the target for each 
> > > > recipient.
> > > qmail does it...
> > The claim is that making separate connections is usually faster (fewer
> > round-trip delays) because of how SMTP works.  It does use more
> > bandwidth but this is unlikely to be significant on most sites,
> > most of the time.
> >
> > These days however, when people send attachments megabytes in size (or
> > viruses do it for them), I don't know whether that claim is still
> > true.
>
> 1. I think it *is* unfair towards the receiving MX to send the same mail 
> multiple times.
>
> 2. I think it is *negligible* for locally generated, private + cron mails.
>
> 3. not trying to aggregate mail delivery on one MX makes the code *SO 
> MUCH EASIER*.  seriously.  think about what you need:
>
> a. central coordination instance
> b. MX/A lookups for all domain parts of all mails
> c. choose one MX
> d. now find all mails which could potentially be sent there
> e. weed out rejects
> f. start over
>
> point is, you can't say "hey, they have the same MXes", because 
> different domains could share only one MX out of three, for example.  
> you have to check for every MX connect which other mails could be 
> delivered there.  definitely not a necessary option for the first round.
>
> cheers
>  simon

Feel free to use these addresses for testing your queing and retry rules on 
multiple recipients et al:

askbill@triligon.to

bill@triligon.to

wbh@triligon.to

postmaster@triligon.to

Typical daily logs are a good test send, as like it or not - some can be 
perceived to have spammish characteristics.

The postmaster address should be found to accept domain-literals, i.e. addressed 
to postmaster@203.194.153.83, IF there are no other addressees on such a message 
(illegal for bounces).  The others will not.

- it is a server dedicated primarily to MTA R&D, (Exim at present) and I can 
give you log extracts if the rejection messages you will certainly get are not 
specific enough.

It should become apparent 'real soon' that building a reliable MTA in the 'spam 
age'  - one that doesn't resemble a zombot -  is a seriously non-trivial exercise.

HTH,

Bill