Emails from yahoo not received

HCL Notes/Domino 8.5 Forum (includes Notes Traveler)

Subject: Emails from yahoo not received

Feedback Type: Problem

Product Area: Domino Server

Technical Area: Administration

Platform: Linux server

Release: 8.5.3

Reproducible: Intermittent

Hi there,

Since last week, we have been getting problems receiving emails from yahoo.
We have a test yahoo email account and we periodically send emails to ourselves for testing.
The error we get on yahoo is:
"Mail server for "xxx.mu" unreachable for too long :"

An internet search revealed that the problem could be with our mx record.
We checked our domain on mxtoolbox.com and it is OK

We checked the server logs and found that yahoo tries to connect but no messages are received:
29/09/2014 15:10:02 SMTP Server: nm10-vm16.bullet.mail.tp2.yahoo.com (203.188.200.246) disconnected. 0 message[s] received
29/09/2014 15:11:33 SMTP Server: nm23.bullet.mail.ir2.yahoo.com (212.82.96.47) disconnected. 0 message[s] received
29/09/2014 15:15:01 SMTP Server: nm1.bullet.mail.ne1.yahoo.com (98.138.90.64) disconnected. 0 message[s] received
29/09/2014 15:15:03 SMTP Server: nm34-vm8.bullet.mail.bf1.yahoo.com (72.30.239.6) disconnected. 0 message[s] received
However, there are exceptions, e.g.
29/09/2014 15:10:02 SMTP Server: omp1016.mail.bf1.yahoo.com (98.139.212.207) disconnected. 1 message[s] received

We checked the I.P.s of the SMTP servers on mxtoolbox's blacklist check and found that all the SMTP servers that did not transfer messages are on at least one international blacklist.
The one that managed to transfer a message is on no international blacklist.
So we contacted the provider of our spam filter and he confirmed that the spam filter processes emails only once they are received... so the problem is 'upstream'.

Emails from gmail.com and hotmail.com are correctly being received at all times.

DNS Blacklist filters is disabled on our server.

We have a firewall but it does not block emails.

Moreover, there is a second separate domain that we administer.
It is on a separate domino server, on a separate virtual machine but on the same physical server.
However, if we send an email from yahoo to an address on that second domain, the mail is received...

Also, we found that this problem with yahoo only happens during our working hours.
Last night at 19:18 I sent an email from yahoo to my Lotus email and it got through.
On Saturday and Sunday also I sent test emails and they were correctly received.
So it seems that the issue occurs during office hours...
We would be very grateful for any help or advice.

Kind regards.

Feedback number WEBB9PFFW9 created by ~Tip Reresagenetsi on 09/30/2014

Status: Closed
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