[Mailman-Users] split incoming mailserver from mailman

[Bill Cole]

On 16 Aug 2012, at 8:33, Marcus Schopen wrote:

> Hi,
>
> I'm looking for a way to separate the incoming mailserver which 
> handles
> the addresses from the mailman instance, which sends mails out. I'm
> running sendmail as MTA. The wrapper in /etc/aliases
> ("|/var/lib/mailman/mail/mailman ...) seems to have no option to
> transport the incoming email e.g. by http requests to a remote mailman
> server. Any ideas?

As is documented, Mailman needs to run on a machine with Python and a 
MTA. The only mechanism for submitting mail to a Mailman list is by 
piping a message to the mailman executable and that is done most easily 
by having the MTA deliver incoming Mailman messages via a piped alias. 
To use another transport, you'd probably have to write the transport 
code yourself.

Having the unfortunate architectural problem of list addresses in a 
domain that has other types of mail which you want to segregate from 
list traffic can be partly mitigated by having the inbound MTA(s) for 
the domain use special-case routing for the list-related addresses. The 
main server can pass mail for those addresses to the Mailman server 
which "delivers" mail for those addresses locally (i.e. through aliases 
that pipe messages to mailman.) Mailman then can send outbound mail via 
its local submission subsystem and whatefver outbound routing that uses 
(i.e. the local MTA or a relaying MTA.)  For Sendmail, that sort of 
arbitrary address routing is probably best done using the mailertable 
feature, with complementary tables on the main MTA server and the 
Mailman server directing each others' addresses appropriately. As with 
anything involving Sendmail there are also other ways to implement that 
which might be convenient if you already are using them (e.g. the 
"mailhub" model, User DB, or handmade custom .cf code) but they would be 
harder fits than the mailertable.