[Mailman-Users] nodupes doesn't seem to be working with aliases

[Mark Sapiro]

On 05/05/2016 04:33 PM, Curtis Villamizar wrote:
> 
> I have a postfix virtual-alias of the form:
> 
>   a    b, c, d
>   c    e, f
>   d    g, h
>   g    i, j
>   h    k, l
> 
> If I send mail to a set of mailing lists then dupes get suppressed but
> not if I send to an alias that expands to the same set of mailing
> lists.  Mailman gets two copies from postfix but the message-id is the
> same for both.  There is a to= and orig_to= in maillog but the
> messages should be otherwise identical including the timestamps.
> 
> Is there a way to suppress dupes in this situation?


Mailman's avoid duplicates setting does nothing about posts to multiple
lists. It only suppresses the list copy to a recipient who is also
directly addressed in To: or Cc:.

If I understand correctly, there's nothing you can do in Mailman about
this. Mailman has a Non-digest options -> regular_exclude_lists feature.

Your "If I send mail to a set of mailing lists then dupes get
suppressed" statement tells me you may already be using this. However,
it depends on the "sibling list" being explicit in To: or Cc: which will
not be the case when the post comes via an alias.


> I have 5 such aliases for convenience but if I can't suppress dupes
> its an annoyance since some people are on multiple mailing lists.  For
> some reason I thought this used to work (but might have imagined it).


If what I say above doesn't satisfactorily explain what you see, I'll
try further, but

1) avoid dups whon't affect this.

2) regular_exclude_lists can help but only if lists are explicitly
addressed. For example, if both c at domain and d at domain are in b at domain's
regular_exclude_lists and d at domain is in c at domain's
regular_exclude_lists, and a post is explicitly addressed to all three
of b at domain c at domain and d at domain, then a regular member of all three
lists will receive the post only from d at domain, a member of the two
lists c at domain and d at domain will receive the post only from d at domain, a
member of the two lists b at domain and d at domain will receive the post only
from d at domain and a member of the two lists b at domain and c at domain will
receive the post only from c at domain

However if the post is addressed to a at domain and forwarded to b, c and d
by an alias, none of b at domain, c at domain or d at domain will be an explicit
To: or Cc: addressee of the post so everyone will receieve a copy from
each list of which they are a member.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan