duplicate suppression, sieve, loops, redirect and lost email

[Ken Murchison]

Quoting Ragnar Sundblad <ragge at nada.kth.se>:

> 
> Hello all,
> 
> Excuse me if I could have found the answers to those questions
> on my own. I actually _have_ searched the list archives and the
> web, but only got more questions. This subject seems to have
> been partly discussed before.
> 
> We are using duplicate suppression and sieve.
> 
> When people do a sieve
>  redirect "<myself>@<mydomain>" (that is, to themselves)
> the email gets sent into the smtp world again, received again
> and duplicate suppressions just silently discards the email
> as has been discussed before.
> 
> This is obviously now what people want, and it is also
> obviously very bad to loose email.

The message in question does not get lost.  It has already been delivered to 
the recipient once.


> I have read that a sieve script could possible cause an
> infinite mail loop if used without duplicate suppression,
> and therefor you need to turn on duplicate suppression if
> you are using sieve. When would that happen?

It shouldn't.  With any recent Cyrus release (2.1.3+ ?) you can disable 
duplicate suppression and still have support for sieve.

I _am_ curious what a sane reason for redirecting an email to one's self is.


> What I would rather assume would happen is that the email
> would loop until sendmail (or whatever mta you are using)
> returns it due to exceeded hop count. Is this not so?

It shouldn't get to this point.

> We are using another machine as a front end mail distrubutor,
> maybe that makes things different for us, but my simple
> experiments and my maybe bad analysis indicates not.
> 
> /ragge
> 
> 
> 
> 


-- 
Kenneth Murchison     Oceana Matrix Ltd.
Software Engineer     21 Princeton Place
716-662-8973 x26      Orchard Park, NY 14127
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