unusual rate of unsolicited mail originating from your IP address

Question

On my server I redirect mail, arriving to in@example.com, to manager1@gmail.com and manager2@gmail.com with /etc/aliases file.

Recently I got the following email in my my.email@gmail.com mailbox (where postmaster@example.com mail is redirected to):

Received: by 10.52.34.73 with SMTP id ...;
        Sun, 27 Apr 2014 03:37:39 -0700 (PDT)
...
Received: from myhost (... [16.19.64.110])
        by mx.google.com with ESMTPS id ...
        for <my.email@gmail.com>
        (version=TLSv1 cipher=RC4-SHA bits=128/128);
        Sun, 27 Apr 2014 03:37:39 -0700 (PDT)
...
Received: from Debian-exim by myhost with local (Exim 4.72)
    id ...
    for postmaster@example.com; Fri, 25 Apr 2014 13:17:05 +0300
...
Date: Fri, 25 Apr 2014 13:17:05 +0300
...
To: postmaster@chatrulez.com

Message frozen

Message 1WddBb-0007hU-1l has been frozen (delivery error message).
The sender is <>.

The following address(es) have yet to be delivered:
  manager1@gmail.com <in@example.com>: SMTP error from remote mail server after MAIL FROM:<> SIZE=1558: host gmail-smtp-in.l.google.com [74.125.201.108]: 530-5.5.1 Authentication Required. Learn more at\n530 5.5.1 http://support.google.com/mail/bin/answer.py?answer=14257 h7sm7285577igy.2 - gsmtp
  manager2@gmail.com <in@example.com>: SMTP error from remote mail server after MAIL FROM:<> SIZE=1558: host gmail-smtp-in.l.google.com [74.125.201.108]: 530-5.5.1 Authentication Required. Learn more at\n530 5.5.1 http://support.google.com/mail/bin/answer.py?answer=14257 h7sm7285577igy.2 - gsmtp

Then I run:

# exigrep -l 1WddBb-0007hU-1l $(find /var/log/exim4 -name 'mainlog*' | sort -rn -t . -k2,2)
2014-04-25 13:17:02 1WddBb-0007hU-1l <= <> H=(115.78.92.64) [118.69.183.136] P=smtp S=522
2014-04-25 13:17:02 1WddBb-0007hU-1l gmail-smtp-in.l.google.com [2a00:1450:4013:c01::1a] Network is unreachable
2014-04-25 13:17:03 1WddBb-0007hU-1l SMTP error from remote mail server after end of data: host gmail-smtp-in.l.google.com [74.125.136.26]: 421-4.7.0 [16.19.64.110      15] Our system has detected an unusual rate of\n421-4.7.0 unsolicited mail originating from your IP address. To protect our\n421-4.7.0 users from spam, mail sent from your IP address has been temporarily\n421-4.7.0 rate limited. Please visit http://www.google.com/mail/help/bulk_mail.\n421 4.7.0 html to review our Bulk Email Senders Guidelines. t3si12446024eeg.301 - gsmtp
2014-04-25 13:17:03 1WddBb-0007hU-1l SMTP error from remote mail server after end of data: host gmail-smtp-in.l.google.com [74.125.136.27]: 421-4.7.0 [16.19.64.110      15] Our system has detected an unusual rate of\n421-4.7.0 unsolicited mail originating from your IP address. To protect our\n421-4.7.0 users from spam, mail sent from your IP address has been temporarily\n421-4.7.0 rate limited. Please visit http://www.google.com/mail/help/bulk_mail.\n421 4.7.0 html to review our Bulk Email Senders Guidelines. x46si12473877eea.209 - gsmtp
2014-04-25 13:17:05 1WddBb-0007hU-1l ** manager2@gmail.com <in@example.com> R=dnslookup T=remote_smtp: SMTP error from remote mail server after MAIL FROM:<> SIZE=1558: host gmail-smtp-in.l.google.com [74.125.201.108]: 530-5.5.1 Authentication Required. Learn more at\n530 5.5.1 http://support.google.com/mail/bin/answer.py?answer=14257 h7sm7285577igy.2 - gsmtp
2014-04-25 13:17:05 1WddBb-0007hU-1l ** manager1@gmail.com <in@example.com> R=dnslookup T=remote_smtp: SMTP error from remote mail server after MAIL FROM:<> SIZE=1558: host gmail-smtp-in.l.google.com [74.125.201.108]: 530-5.5.1 Authentication Required. Learn more at\n530 5.5.1 http://support.google.com/mail/bin/answer.py?answer=14257 h7sm7285577igy.2 - gsmtp
2014-04-25 13:17:05 1WddBb-0007hU-1l Frozen (delivery error message)
2014-04-25 13:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 14:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 14:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 15:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 15:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 16:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 16:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 17:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 17:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 18:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 18:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 19:07:58 1WddBb-0007hU-1l Message is frozen
2014-04-25 19:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 20:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 20:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 21:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 21:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 22:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 22:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 23:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-25 23:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 00:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 00:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 01:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 01:37:58 1WddBb-0007hU-1l Message is frozen
2014-04-26 02:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 02:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 03:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 03:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 04:07:38 1WddBb-0007hU-1l Message is frozen
2014-04-26 04:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 05:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 05:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 06:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 06:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 07:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 07:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 08:07:58 1WddBb-0007hU-1l Message is frozen
2014-04-26 08:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 09:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 09:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 10:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 10:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 11:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 11:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 12:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 12:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 13:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 13:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 14:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 14:37:58 1WddBb-0007hU-1l Message is frozen
2014-04-26 15:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 15:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 16:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 16:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 17:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 17:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 18:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 18:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 19:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 19:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 20:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 20:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 21:07:58 1WddBb-0007hU-1l Message is frozen
2014-04-26 21:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 22:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 22:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 23:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-26 23:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 00:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 00:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 01:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 01:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 02:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 02:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 03:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 03:37:58 1WddBb-0007hU-1l Message is frozen
2014-04-27 04:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 04:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 05:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 05:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 06:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 06:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 07:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 07:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 08:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 08:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 09:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 09:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 10:07:58 1WddBb-0007hU-1l Message is frozen
2014-04-27 10:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 11:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 11:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 12:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 12:37:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 13:07:37 1WddBb-0007hU-1l Message is frozen
2014-04-27 13:37:37 1WddBb-0007hU-1l Unfrozen by errmsg timer
2014-04-27 13:37:38 1WddBb-0007hU-1l => manager2@gmail.com <in@example.com> R=dnslookup T=remote_smtp H=gmail-smtp-in.l.google.com [74.125.136.27] X=TLS1.0:RSA_ARCFOUR_SHA1:16 DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=mx.google.com"
2014-04-27 13:37:38 1WddBb-0007hU-1l -> manager1@gmail.com <in@example.com> R=dnslookup T=remote_smtp H=gmail-smtp-in.l.google.com [74.125.136.27] X=TLS1.0:RSA_ARCFOUR_SHA1:16 DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=mx.google.com"
2014-04-27 13:37:38 1WddBb-0007hU-1l Completed

2014-04-25 13:17:05 1WddBd-0007hk-1p <= <> R=1WddBb-0007hU-1l U=Debian-exim P=local S=1111
2014-04-25 13:17:06 1WddBd-0007hk-1p ** my.email@gmail.com <postmaster@chatrulez.com> R=dnslookup T=remote_smtp: SMTP error from remote mail server after MAIL FROM:<> SIZE=2150: host gmail-smtp-in.l.google.com [74.125.201.109]: 530-5.5.1 Authentication Required. Learn more at\n530 5.5.1 http://support.google.com/mail/bin/answer.py?answer=14257 p7sm7216866igg.15 - gsmtp
2014-04-25 13:17:06 1WddBd-0007hk-1p Frozen (delivery error message)
2014-04-25 13:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 14:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 14:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 15:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 15:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 16:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 16:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 17:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 17:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 18:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 18:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 19:07:58 1WddBd-0007hk-1p Message is frozen
2014-04-25 19:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 20:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 20:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 21:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 21:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 22:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 22:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 23:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-25 23:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 00:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 00:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 01:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 01:37:58 1WddBd-0007hk-1p Message is frozen
2014-04-26 02:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 02:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 03:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 03:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 04:07:38 1WddBd-0007hk-1p Message is frozen
2014-04-26 04:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 05:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 05:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 06:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 06:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 07:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 07:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 08:07:58 1WddBd-0007hk-1p Message is frozen
2014-04-26 08:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 09:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 09:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 10:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 10:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 11:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 11:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 12:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 12:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 13:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 13:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 14:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 14:37:58 1WddBd-0007hk-1p Message is frozen
2014-04-26 15:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 15:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 16:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 16:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 17:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 17:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 18:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 18:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 19:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 19:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 20:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 20:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 21:07:58 1WddBd-0007hk-1p Message is frozen
2014-04-26 21:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 22:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 22:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 23:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-26 23:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 00:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 00:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 01:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 01:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 02:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 02:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 03:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 03:37:58 1WddBd-0007hk-1p Message is frozen
2014-04-27 04:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 04:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 05:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 05:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 06:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 06:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 07:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 07:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 08:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 08:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 09:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 09:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 10:07:58 1WddBd-0007hk-1p Message is frozen
2014-04-27 10:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 11:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 11:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 12:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 12:37:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 13:07:37 1WddBd-0007hk-1p Message is frozen
2014-04-27 13:37:38 1WddBd-0007hk-1p Unfrozen by errmsg timer
2014-04-27 13:37:39 1WddBd-0007hk-1p => my.email@gmail.com <postmaster@chatrulez.com> R=dnslookup T=remote_smtp H=gmail-smtp-in.l.google.com [74.125.136.27] X=TLS1.0:RSA_ARCFOUR_SHA1:16 DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=mx.google.com"
2014-04-27 13:37:39 1WddBd-0007hk-1p Completed

First of all, I have problems interpreting it.

We got bounce message from 118.69.183.136. But why does it bounce to both manager1@gmail.com and manager2@gmail.com? Did they both send an email, which could not be delivered? Unlikely.

Then google replies with "421-4.7.0 [16.19.64.110 15] Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been temporarily rate limited. Please visit http://www.google.com/mail/help/bulk_mail.html to review our Bulk Email Senders Guidelines." What is this supposed to mean? in@example.com is a feedback mailbox, redirected to manager1@gmail.com and manager2@gmail.com. I doubt they send a lot of emails. Would you suggest a way to count them?

As a result one more bounce message is generated for postmaster@example.com. But now google replies with "530-5.5.1 Authentication Required. Learn more at http://support.google.com/mail/bin/answer.py?answer=14257" That I don't understand either. I now can send messages to postmaster@example.com just fine.

In the end, the bounce messages get delivered. I'm running debian 6. Could you explain me what's going on and what am I to do?

If you want to control your corporate email, **host your corporate email**. Simply forwarding things to gmail isn't going to give you much control, and honestly, you'll spend more time sorting things like this out - because you have no view into, nor control over, google's corporate decisions. — MadHatter, Apr 28 '14 at 22:14
As a side note, you should also consider that if any of your users mark email in their gmail box as spam, because you forwarded the email, your server will be considered the responsible server and will contribute to possibly being blocked (or have email filtered via Blatant Spam Blocking a la Postini). I have one user that insists on using AOL that I keep having to reeducate to not mark things as spam once they get to AOL or it will block us. — MikeAWood, Apr 29 '14 at 01:47
I agree, but having mailboxes on `gmail` has its advantages, don't you think? Like you don't need a mail client to access them. Also, they filter spam for you. Probably there are more. For now I have only two users, receiving mail for that server. — x-yuri, Apr 29 '14 at 06:30
You don't need a mail client to access mailboxes on **any** mail server; that's what IMAP and POP are for (especially when wrapped in SSL). Spam filtering is again something where control is much more important than convenience; look at the number of questions on SF about "*gmail receives my mails but they never show up in the user's mailbox*" if you doubt that. And if you think "*only two users*" isn't much of a problem, look how much trouble they're causing you right now. — MadHatter, Apr 29 '14 at 08:30
`You don't need a mail client to access mailboxes on any mail server; that's what IMAP and POP are for ` How come? [Wikipedia](http://en.wikipedia.org/wiki/Post_Office_Protocol) says: "the Post Office Protocol (POP) is an application-layer Internet standard protocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection" — x-yuri, Apr 30 '14 at 18:30
"I agree, but having mailboxes on gmail has its advantages, don't you think?" So pay for Google Apps for Business, which lets you have Gmail for your own domain name. — ceejayoz, May 01 '14 at 11:58
Sorry, x-yuri, I misunderstood what you meant by "*you don't need a mail client to access [gmail]*". You meant you can read your mail via the web, so needed no software besides a web browser, yes? If so, that's true for any decent mail server: just add squirrelmail, or any one of a host of webmail systems. — MadHatter, May 01 '14 at 12:13

score 5 · Answer 1 · answered Apr 28 '14 at 22:41

5

We got bounce message from 118.69.183.136. But why does it bounce to both manager1@gmail.com and manager2@gmail.com? Did they both send an email, which could not be delivered? Unlikely.

It isn't bouncing to the two addresses, it's bouncing it to postmaster telling you that delivery to those two addresses failed.

Then google replies with "421-4.7.0 [16.19.64.110 15] Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been temporarily rate limited. Please visit http://www.google.com/mail/help/bulk_mail.html to review our Bulk Email Senders Guidelines." What is this supposed to mean?

It means you have been rate limited. You should go to the URL stated for more information. What part of that is unclear?

I doubt they send a lot of emails. Would you suggest a way to count them?

You're barking up the wrong tree. The message clearly states that your IP address is sending too many emails. This has nothing to do whom the messages are to or from, it's simply the number of messages from that exact IP address (your server) that are being sent to google. This includes your messages that are being generated to postmaster due to bounces/failures that are being forwarded to your gmail account.

You should realize you have a catch-22 here that if Google is limiting the amount of messages from your system to theirs and you have your errors (bounces, warnings) going to google as well..

In the end, the bounce messages get delivered. I'm running debian 6. Could you explain me what's going on and what am I to do?

You've sent enough messages from your IP to gmail servers and Google has temporarily (as it clearly says in the logs) rate limited. Those messages are generating errors (warnings) that they could not be immediately delivered. You then have those messages being forwarded to yet another gmail address which is creating even more attempts to send email through google's servers from your IP which is likely making the problem worse.

Once their temporary rate limiting has been lifted then your messages would go through as expected.

and what am I to do?

You should follow the guidelines that Google already gave you in the error message.
You should stop forwarding postmaster mail to google to keep the number of messages from your system to them down.

If those fail, you should consider paying Google to host the domain properly and/or stop forwarding messages to gmail accounts.

answered Apr 28 '14 at 22:41

Thanks for your reply. But I still have some things I wanted to clarify. The big picture is that google received a lot of emails from my server, so it started to rate limit messages. After that some user sends an email to `in@domain.com` and have to get back a bounce message, right? So why do I get bounce message (`1WddBb-0007hU-1l`)? Also, why do I get authentication error in the second message? – x-yuri Apr 29 '14 at 06:49
1

When a message gets frozen in exim, only an admin can thaw that message to either remove it or retry delivery. postmaster is the obvious place to be notified of that. A message typically gets frozen when delivery isn't possible and neither is the bounce. An example would be someone sending to one of your addresses that gets forwarded and their FROM address is also an address (any address) that also goes to google/gmail. If you can't send the first message because of the throttling, you obviously can't send a bounce/warning to the same place.. because of throttling. Frozen message. – Apr 29 '14 at 17:43
Wait, you say the first of my messages is not a bounce? Why does it have no sender address then? `2014-04-25 13:17:02 1WddBb-0007hU-1l <= <> H=(115.78.92.64) [118.69.183.136]` – x-yuri Apr 30 '14 at 19:17
1

It was generated from your MTA (exim), not an MUA/user so there is no address listed. A bounce is the original message returned to the sender, typically due to delivery problems. This is not that as the message was sent to the administrator of the server, not the original sender. – Apr 30 '14 at 19:22
There are two messages there. The first one (`1WddBb-0007hU-1l`) is received over `SMTP` (`P=smtp`), the second one (`1WddBd-0007hk-1p`) is locally generated (`P=local`). Why is the first email (locally generated from your words) received over `SMTP`? That may be if it's a bounce of locally generated email. – x-yuri Apr 30 '14 at 19:39
Also, judging by the first message being forwarded to managers, its destination must be `in@domain.com`. – x-yuri Apr 30 '14 at 19:46
A message was received by the system, via smtp (1l). It tried to send that message to the two addresses you are forwarding to. That was rejected by google because of rate limiting. Without seeing either the message or your config I'm not exactly sure what the 1p one is, but my guess is it's due to having an `errors_address` sent. All of this is covered in detail in the documentation. [Here's the page on logs](http://www.exim.org/exim-html-current/doc/html/spec_html/ch-log_files.html). – Apr 30 '14 at 19:57
The message (`1l`) was received by system via `smtp` and has no sender address. You say it's not a bounce. *Why then there is no sender address there?* What is the second message is more or less clear, you said it yourself, it's a notification about frozen message. [My config](http://sprunge.us/aPKO), just in case. I can't supposedly show you the `1l` message, it's not in the queue anymore. Also, I read the documentation before asking the question. It's just that it didn't answer all my questions. – x-yuri May 05 '14 at 14:59
A bounce is when the original message is returned to the sender as undeliverable. A message marked as frozen isn't returned, it's stuck in the as frozen until it's thawed (manually or by a timer configured). If the message is not a failure notice delivered to the original person, it's not a bounce. I'm about 99% sure what you have here are errors from messages that were attempted to be bounced but the bounce message failed to deliver to (because you're forwarding your postmaster gmail also). As a professional, these distinctions are important when asking for help. – May 05 '14 at 18:09

Sherwood Botsford · Answer 2 · 2021-03-17T17:15:48.860

Yeah, yeah, this is a 6 year old question.

However, I found that if you have a mail loop, this is the message you get. I had a set of filters where my business domain forwarded to my personal gmail. and my gmail forwarded back to my business.

Google is pretty good at detecting loops, so it doesn't trip every time. But one time after reworking my filter setup I got this problem for about 2 weeks intermittently. Curiously the error message ranged from nearly instant to several days after the original message.

unusual rate of unsolicited mail originating from your IP address

2 Answers2