The mailing list for listmasters using Sympa

[Tom Fillmore <address@concealed>]

Hi -

I have the same problem with yahoo and AOL.  There are a couple ways to 
get messages through, at least most of the time:

* DKIM/SPF for the domain - without it probably nothing will go in large 
amounts (in the case of yahoo in the US, >=20 messages at once.  Always 
have the DKIM feature turned on for all messages you send, per list.  I 
also have it correctly configured in postfix, so my mails are signed 
twice.  There's no penalty for that.

* Whitelisting.  Good look with that.  AOL changes their mind pretty 
much daily, I've had first hand experience where they OK it one day, 
then have the same problem the next day.  Yahoo is about the same - they 
want your DARPA address  to whitelist, they NEVER respond back to 
requests for help and they are really really inconsistent; as far as I 
can tell their servers get really out of sync.  Case in point - one 
large distribution (10k+ recipients) was blocked for more than one half 
of all yahoo recipients in the US, while the others got their message.  
I asked for some mails from those who did and didn't get their messages, 
some were rejected _by the same exact server_, while others got through, 
with some rejection timestamps about an hour apart.  Ironically (maybe 
not?) all the Canadian recipients got their message.  Every single one.  
This was about 20% of the total.

* Throttle your mail server.  This is a really bad thing to do in 
general but with AOL and Yahoo not being consistent and returning mails 
with an error of 'too many messages', or similar, this is beginning to 
look like a viable alternative.

Other than that I'm out of ideas but would love to hear what others do.

Tom Fillmore
southern California


On 09/02/2015 09:39 AM, Amos (via sympa-users Mailing List) wrote:
> I know there are more than a few on here using Sympa that have their
> student population in the cloud with Office365.  My question to y'all:
> have you had to do anything special with message delivery to avoid MS
> from blocking your Sympa traffic to your students?
>
> One of our major distributions got blocked by MS, and just trying to
> figure out better ways to handle that traffic to avoid problems in the
> future.  I know they have their guidelines, but so far it seems
> somewhat arbitrary what they are blocking and what they aren't, and of
> course they aren't being very forthcoming about the details.
>
> Thanks in advance,
> Amos