[Mailman-Users] Ongoing delivery issues - First Yahoo, now AOL
minxmertzmomo at gmail.com
Sat Mar 8 15:07:50 CET 2008
On Fri, Mar 7, 2008 at 2:58 PM, Mark Sapiro <mark at msapiro.net> wrote:
> Rick Harris wrote:
> >I posted a couple of weeks ago regarding mail not being delivered to Yahoo
> >addresses. I've all but written that off as an Internet black hole.
> >Messages from my list almost never make it to Yahoo recipients. If I post
> >to the list, and cc a Yahoo address, then that works fine. Background noise
> >only, none of this matters today.
> Since your original post on this issue, I have looked at my maillog and
> I see lots of these
> host e.mx.mail.yahoo.com[220.127.116.11] refused to talk to me: 421 4.7.0
> [TS01] Messages from 18.104.22.168 temporarily deferred due to user
> complaints - 22.214.171.124; see http://postmaster.yahoo.com/421-ts01.html
> type messages (3500 in the last month, but only 46 in the last 5 days).
> I also get lots of
> host g.mx.mail.yahoo.com[126.96.36.199] said: 451 Message temporarily
> deferred -  (in reply to end of DATA command)
> host c.mx.mail.yahoo.com[188.8.131.52] said: 421 Message temporarily
> deferred - 4.16.51. Please refer to
> http://help.yahoo.com/help/us/mail/defer/defer-06.html (in reply to
> end of DATA command)
> host c.mx.mail.yahoo.com[184.108.40.206] refused to talk to me: 421
> Message temporarily deferred - 220.127.116.11. Please refer to
This is greylisting:
in which the receiving MTA responds with a temporary failure to
suspicious or unknown senders. It kills a lot of spam, because most
spam is sent by non-compliant MTAs that don't bother retrying.
> The important thing is that in my case at least, every one of these is
> successfully retried, either immediately via a different MX or after 1
> or a few delayed retries. All of these messages were eventually
> accepted by Yahoo and I have gotten zero complaints of missing mail
> from Yahoo list members.
> Perhaps there is some issue with your outbound MTA not retrying these
> 421 and 451 status returns.
Ditto. Rick, are you in charge of your MTA? One way or another, you
should figure out how your MTA handles temporary failures and retries.
More information about the Mailman-Users