==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 0.9.8
- Linux/BSD distribution name and version: Ubuntu 16 LTS
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): Mysql
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No - But thinking we will  - easier.. :-)
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

This is the setup.

Public IP>>firewall/SMTP Proxy>>iredmail server (10.100.100.70)

The private internal IP of the firewall/proxy is 10.100.100.1

If we connect to sogo front end, either via the private IP of the iredmail server(https://10.100.100.70/sogo/, on the local LAN OR connecting to sogo via the public IP (through the firewall), we can send and receive email no problem to external and internal accounts. (by internal i mean emailing to myself or another user setup on iredmail)

However, if we use an IMAP client (mac mail) that connects to the iredmail server on its private IP (10.100.100.70)

We get a bounceback if we try to email ourselves or another user on iredmail server.

The error we WERE getting yesterday was an SMTP AUTH error, shown below. (The sogo client was ok, just the IMAP client was failing)

Dec  6 16:13:00 host1 postfix/postscreen[12198]: CONNECT from [10.100.100.1]:53738 to [10.100.100.70]:25
Dec  6 16:13:00 host1 postfix/postscreen[12198]: PASS OLD [10.100.100.1]:53738
Dec  6 16:13:00 host1 postfix/smtpd[12199]: connect from unknown[10.100.100.1]
Dec  6 16:13:00 host1 postfix/smtpd[12199]: Anonymous TLS connection established from unknown[10.100.100.1]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
Dec  6 16:13:00 host1 postfix/smtpd[12199]: NOQUEUE: reject: RCPT from unknown[10.100.100.1]: 554 5.7.1 <accounts@voiprofessional.com>: Recipient address rejected: SMTP AUTH is required for users under this sender domain; from=<accounts@voiprofessional.com> to=<accounts@voiprofessional.com> proto=ESMTP helo=<mail2.santoratech.com>
Dec  6 16:13:00 host1 postfix/smtpd[12199]: disconnect from unknown[10.100.100.1] ehlo=2 starttls=1 mail=1 rcpt=0/1 data=0/1 rset=1 quit=1 commands=6/8

However today the problem has gone away...we have no idea why.

Generally if you can send ok from the web client (sogo) but an IMAP client connecting to the iredmail server directly fails, is this really an imap client issue only, or a iredmail issue? (just for future reference)

BTW MX records, DNS all seem to be ok, as the webmail client works ok, so i figured i can rule that out.
Sorry for the strange question, but any help or advice is appreciated. thanks

Here is a log of sending using webmail client sogo: working.

Dec  7 11:21:30 host1 postfix/postscreen[28410]: CONNECT from [127.0.0.1]:47398 to [127.0.0.1]:25
Dec  7 11:21:30 host1 postfix/postscreen[28410]: WHITELISTED [127.0.0.1]:47398
Dec  7 11:21:30 host1 postfix/smtpd[28413]: connect from localhost[127.0.0.1]
Dec  7 11:21:30 host1 postfix/smtpd[28413]: CD975540608: client=localhost[127.0.0.1]
Dec  7 11:21:30 host1 postfix/cleanup[28424]: CD975540608: message-id=<65d-5c0a5780-3-635d8900@182014036>
Dec  7 11:21:30 host1 postfix/qmgr[2379]: CD975540608: from=<accounts@voiprofessional.com>, size=962, nrcpt=1 (queue active)
Dec  7 11:21:30 host1 postfix/smtpd[28413]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Dec  7 11:21:43 host1 postfix/10025/smtpd[28738]: connect from localhost[127.0.0.1]
Dec  7 11:21:43 host1 postfix/10025/smtpd[28738]: 207A254060C: client=localhost[127.0.0.1]
Dec  7 11:21:43 host1 postfix/cleanup[28424]: 207A254060C: message-id=<65d-5c0a5780-3-635d8900@182014036>
Dec  7 11:21:43 host1 postfix/qmgr[2379]: 207A254060C: from=<accounts@voiprofessional.com>, size=2069, nrcpt=1 (queue active)
Dec  7 11:21:43 host1 postfix/10025/smtpd[28738]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Dec  7 11:21:43 host1 amavis[14917]: (14917-03) Passed CLEAN {RelayedInternal}, MYNETS LOCAL [127.0.0.1]:47398 <accounts@voiprofessional.com> -> <accounts@voiprofessional.com>, Queue-ID: CD975540608, Message-ID: <65d-5c0a5780-3-635d8900@182014036>, mail_id: ybdyVCgVDHHz, Hits: -0.999, size: 962, queued_as: 207A254060C, dkim_new=dkim:globecastmt.com, 12255 ms, Tests: [ALL_TRUSTED=-1,HTML_MESSAGE=0.001]
Dec  7 11:21:43 host1 postfix/amavis/smtp[28431]: CD975540608: to=<accounts@voiprofessional.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=12, delays=0.09/0/0.01/12, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 207A254060C)
Dec  7 11:21:43 host1 postfix/qmgr[2379]: CD975540608: removed
Dec  7 11:21:43 host1 postfix/pipe[28739]: 207A254060C: to=<accounts@voiprofessional.com>, relay=dovecot, delay=0.04, delays=0/0.02/0/0.02, dsn=2.0.0, status=sent (delivered via dovecot service)
Dec  7 11:21:43 host1 postfix/qmgr[2379]: 207A254060C: removed

Here is a log using an IMAP client: working today.

Dec  7 11:22:23 host1 postfix/postscreen[28410]: CONNECT from [10.100.100.1]:57476 to [10.100.100.70]:25
Dec  7 11:22:23 host1 postfix/postscreen[28410]: PASS OLD [10.100.100.1]:57476
Dec  7 11:22:23 host1 postfix/smtpd[28413]: connect from unknown[10.100.100.1]
Dec  7 11:22:23 host1 postfix/smtpd[28413]: Anonymous TLS connection established from unknown[10.100.100.1]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
Dec  7 11:22:23 host1 postfix/smtpd[28413]: BFB17540608: client=unknown[10.100.100.1]
Dec  7 11:22:23 host1 postfix/cleanup[28424]: BFB17540608: message-id=<9EBF77EB-88C9-4E3B-BF35-09644E341839@voiprofessional.com>
Dec  7 11:22:23 host1 postfix/qmgr[2379]: BFB17540608: from=<accounts@voiprofessional.com>, size=1065, nrcpt=1 (queue active)
Dec  7 11:22:23 host1 postfix/smtpd[28413]: disconnect from unknown[10.100.100.1] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7
Dec  7 11:22:23 host1 postfix/10025/smtpd[28738]: connect from localhost[127.0.0.1]
Dec  7 11:22:23 host1 postfix/10025/smtpd[28738]: E981454060C: client=localhost[127.0.0.1]
Dec  7 11:22:23 host1 postfix/cleanup[28424]: E981454060C: message-id=<9EBF77EB-88C9-4E3B-BF35-09644E341839@voiprofessional.com>
Dec  7 11:22:23 host1 postfix/10025/smtpd[28738]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Dec  7 11:22:23 host1 postfix/qmgr[2379]: E981454060C: from=<accounts@voiprofessional.com>, size=1574, nrcpt=1 (queue active)
Dec  7 11:22:23 host1 amavis[14915]: (14915-05) Passed CLEAN {RelayedInbound}, [10.100.100.1]:57476 <accounts@voiprofessional.com> -> <accounts@voiprofessional.com>, Queue-ID: BFB17540608, Message-ID: <9EBF77EB-88C9-4E3B-BF35-09644E341839@voiprofessional.com>, mail_id: AxxyNRSTJVqr, Hits: -1, size: 1065, queued_as: E981454060C, 167 ms, Tests: [ALL_TRUSTED=-1]
Dec  7 11:22:23 host1 postfix/amavis/smtp[28431]: BFB17540608: to=<accounts@voiprofessional.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=0.19, delays=0.02/0/0/0.17, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as E981454060C)
Dec  7 11:22:23 host1 postfix/qmgr[2379]: BFB17540608: removed
Dec  7 11:22:23 host1 postfix/pipe[28739]: E981454060C: to=<accounts@voiprofessional.com>, relay=dovecot, delay=0.04, delays=0/0.01/0/0.03, dsn=2.0.0, status=sent (delivered via dovecot service)
Dec  7 11:22:23 host1 postfix/qmgr[2379]: E981454060C: removed

We did the following actions yesterday based on the docs. Can you tell me if this is ok or bad?

1.to add the smtp proxy to the whitelist, and checked using:

python /opt/iRedAPD-2.2/tools/wblist_admin.py --add --whitelist 10.100.100.1

python /opt/iRedAPD-2.2/tools/wblist_admin.py --list --whitelist
* Establishing SQL connection.
* List all inbound whitelist for account: @.
/usr/lib/python2.7/dist-packages/pymysql/cursors.py:158: Warning: '@@tx_isolation' is deprecated and will be removed in a future release. Please use '@@transaction_isolation' instead
  result = self._query(query)
10.100.100.1

We also added the following to the /opt/iredmail/settings.py file

# Steve Added to try to stop the following error:
# "Recipient address rejected: SMTP AUTH is required for users under this sender domain"
MYNETWORKS = ['10.100.100.1']

So to be clear, today it seems emails are all working now, but we don't know why they were not before.

Thank you so much..