[Mailman-Users] Dealing with rate limiting from Roadrunner/Time Warner

[Mark Sapiro]

On 05/15/2014 06:46 AM, Conrad G T Yoder wrote:
> 
> It is a true bounce - mail is being rejected.  The error message is phrased as a "temporary failure," but the message is bounced at the SMTP transaction.  “At some point,” they stop bouncing.  RR won’t say when that happens.
> 
> 
> <user at roadrunner.com>: delivery temporarily suspended: host
>    cdptpa-pub-iedge-vip.email.rr.com[107.14.166.70] refused to talk to me: 421
>    4.7.1 - Connection refused - <66.33.216.56> -  Too many concurrent
>    connections ( <2> ) from source IP


This is a 4xx status, so it is a temp failure, and Mailman should be
retrying these.

It looks like what is going on is the outgoing MTA has received multiple
messages from Mailman for RR recipients, and is trying to send them in
parallel.

The bottom line is that these messages should be ultimately delivered.

Note that if my analysis is correct, it would appear that Mailman is
already sending 1 message per recipient to the outgoing MTA because  of
personalization or VERP enabled or SMTP_MAX_RCPTS = 1, and this is a
case where a larger SMTP_MAX_RCPTS and no VERP or personalization might
help.

Unfortunately, the only one of these things that *might* be available to
a list owner is personalization.

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