[Mailman-Users] control mail distribution ..

[Khalil Abbas]

I'm discussing this with my service provider right now.. I'll tell u what 
comes up..

by the way, what's the default value for SMTP_MAX_RCPTS ??

Thanks..

-----Original Message----- 
From: Mark Sapiro
Sent: Monday, January 24, 2011 9:00 PM
To: Khalil Abbas ; mailman-users at python.org
Subject: Re: [Mailman-Users] control mail distribution ..

Khalil Abbas wrote:
>
>checking some random files in the /var/spool/mailman/bounces/*.pck I found 
>:
>
>******************
>This is the qmail-send program at ______________.\nI\'m afraid I wasn\'t
>able to deliver your message to the following addresses.\nThis is a
>permanent error; I\'ve given up. Sorry it didn\'t work out.\n\n<___________
>(hotmail.fr address) >:\nConnected to 65.54.188.110 but sender was
>rejected.\nRemote host said: 421 RP-001 Unfortunately, some messages from
>____________ weren\'t sent. Please try again. We have limits for how many
>messages can be sent per hour and per day. You can also refer to
>http://mail.live.com/mail/troubleshooting.aspx#errors.\nI\'m not going to
>try again; this message has been in the queue too long.
>******************
>
>checking the error code 421 RP-001 on hotmail I found:
>
>***************
>The mail server IP connecting to Windows Live Hotmail server has exceeded
>the rate limit allowed. Reason for rate limitation is related to IP/domain
>reputation. If you are not an email/network admin please contact your
>Email/Internet Service Provider for help.
>***************
>
>so it is a rate limit no?


Yes it is. But, hotmail is limiting the rate by returning a 421 status
which is retryable, but qmail on the relay host is either giving up
too soon, or you will never be able to deliver all your mail no matter
what you do.


>what can be done about this? it says something about ip/domain reputation,
>is it my domain's reputation or my service provider's relay server's
>reputation?


It's your service provider's relay server. I'm surprised they haven't
cut you off. Consider that hotmail is rate limiting that server and
rejecting (with 421) mail over the limit. This would affect not only
your list mail, but mail to hotmail from any other customer of the
service provider being sent at the same time.

Now, consider what is happening. The relay server gives up retrying the
421 because the "message has been in the queue too long". Either it's
"give up" time is way to short, something only the service provider
can adjust, but maybe you can tell from when the rejected message was
sent, or it keeps retrying for more than a day. If the latter, the
implication would seem that hotmail's rate limit does not allow for
all the days messages to be delivered in a day. The only solution to
that is to get hotmail to raise the rate limit, and only the service
provider can do that.

Now, there is one other point. When you resubscribed, you got all your
notices, so mail sent to one recipient at a time seems to get through.
You can cause Mailman to send more messages with fewer recipients per
message by putting say

SMTP_MAX_RCPTS = 10

in mm_cfg.py. That may help. Otherwise, I don't think there's much you
can do except maybe convince your customers to reduce the frequency of
their announcements.

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