The mailing list for listmasters using Sympa

[Aumont - Comite Reseaux des Universites <address@concealed>]

Marcel wrote:
> We have several somewhat larger lists with
> 200,000 to 500,000 subscribers, growing.

Of course you need a good server with large bandwith.
You also need to tune your Unix system to prevent
"not enought memory", "too many open file", "too many processes"
ands so on when making "maxsmtp" too a hight value. The value you
can use for maxsmtp depend on the server memory size but also depends
of the MTA you are using. With 1giga RAM, sendmail, linux you can use
maxsmtp up to 500 or 1000.

Somme tunning of sendmail is also usefull : teh first one is needed
even for rather small servers : use nocanonify m4 feature. Otherwise
you may need hour and hours if some major DNS server become slow.
The second one is to use multiple spools to keep each spool rather
small. We are using sendmail mutiple spool feature but also crontab
move old message in special spools processed by a specific sendmail
(sendmail -q6h is good enought for message that could not be processed
during the first hour)

You need also to fix your goal :

 -distribute the message as fast as possible.
OR
 -make sympa available for other task as soon as possible ?

> These are "announcement only newletter-type " 

In this case you can keep outgoing message process rather slow but install
a second sympa that will share all it's configuration with the first one but
will process different spool. One  deamon will receive messages adressed
to sympa the other will distribute message received to the list adress .

This way, when some subscribers unsubscribe from the huge list they will
not have to wait for the  distribution process to receive confirmation
from Sympa.


>Would it be possible to have the bounces go to a
>different machine?

You just need to hack 2 lines from List.pm in order to change
"error-to" and the "return-path" headers. here they are :

 $hdr->add('Errors-to', "$name-owner\@$host");

 $data->{'return_path'} ||= "$name-owner\@$self->{'admin'}{'host'}";


>And apart from that: Can sympa handle the mail sending?

No sympa does not do it.


Sympa 4.0 will include some changes to make life easy with large list

-auto remouving of bouncing address
-when distributing a message to a large list, first do it for email adress
 without bounces.
-when sending message to bouncind address do it without the
 "interactive" sendmail option (ie put the mail in spool without starting
 a smtp connection)
-use a option to control how many sympa.pl deamon are needed insteed of
 only one as now.

Serge