1

Topic: Recipient address rejected: User unknown;

==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):
1.2.1 MARIADB edition.
- Deployed with iRedMail Easy or the downloadable installer?
downloadable
- Linux/BSD distribution name and version:
NAME="CentOS Linux"
VERSION="8 (Core)"
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):
MySQL
- Web server (Apache or Nginx):
Nginx
- Manage mail accounts with iRedAdmin-Pro?
No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Jun  9 11:03:11 mail postfix/smtpd[6971]: disconnect from unknown[x.x.x.x] ehlo=2 starttls=1 mail=1 rcpt=0/1 quit=1 commands=5/6
Jun  9 11:04:04 mail postfix/smtpd[6739]: disconnect from unknown[x.x.x.x] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7
Jun  9 11:07:24 mail postfix/anvil[6741]: statistics: max connection rate 2/60s for (smtpd:x.x.x.x) at Jun  9 10:59:04
Jun  9 11:07:24 mail postfix/anvil[6741]: statistics: max connection count 1 for (smtpd:x.x.x.x) at Jun  9 10:58:21
Jun  9 11:07:24 mail postfix/anvil[6741]: statistics: max cache size 1 at Jun  9 10:58:21
Jun  9 11:12:03 mail clamd[2288]: SelfCheck: Database status OK.
Jun  9 11:22:03 mail clamd[2288]: SelfCheck: Database status OK.
Jun  9 11:32:03 mail clamd[2288]: SelfCheck: Database status OK.
Jun  9 11:33:22 mail postfix/postscreen[7585]: CONNECT from [x.x.x.x]:23965 to [y.y.y.y]:25
Jun  9 11:33:22 mail postfix/postscreen[7585]: PASS OLD [x.x.x.x]:23965
Jun  9 11:33:22 mail postfix/smtpd[7588]: connect from unknown[x.x.x.x]
Jun  9 11:33:22 mail postfix/smtpd[7588]: Anonymous TLS connection established from unknown[x.x.x.x]: TLSv1.2 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)
Jun  9 11:33:22 mail postfix/smtpd[7588]: NOQUEUE: reject: RCPT from unknown[x.x.x.x]: 550 5.1.1 <sandorsz@y.y.y.y>: Recipient address rejected: User unknown; from=<sandorsz@birosag.hu> to=<sandorsz@y.y.y.y> proto=ESMTP helo=<levelezes.example.com>

But the postmaster user recieve email:

Thank You!

----

Spider Email Archiver: On-Premises, lightweight email archiving software developed by iRedMail team. Supports Amazon S3 compatible storage and custom branding.

2

Re: Recipient address rejected: User unknown;

Are you trying to send an email to user@ip-address instead of user@domain.com ?

3

Re: Recipient address rejected: User unknown;

szabolcssandor wrote:

Jun  9 11:33:22 mail postfix/smtpd[7588]: NOQUEUE: reject: RCPT from unknown[x.x.x.x]: 550 5.1.1 <sandorsz@y.y.y.y>: Recipient address rejected: User unknown; from=<sandorsz@birosag.hu> to=<sandorsz@y.y.y.y> proto=ESMTP helo=<levelezes.example.com>

The to address "sandorsz@y.y.y.y" doesn't exist on your server.
As @PaulCahill mentioned, is the "y.y.y.y" an IP address?

4

Re: Recipient address rejected: User unknown;

I tried to send email to user@ip_address, the virtual domain doesn't registered at any dns server. What if  I would like to use without Dns registration the mail server.

I am a little confused with DNS registration. What should I do to work the mail server.
- how many dns server should I registered?
- enough one registration for the server and the virtual domain will be  resolved by it or all virtual domain have to be registered at a DNS  server?

For example if i registered example.com as host server, then I create  a virtual domain on iredmail mail.example.com, the postfix mta could work fine?

Thank you for your help?

5 (edited by MuPp3t33r 2020-06-12 21:02:48)

Re: Recipient address rejected: User unknown;

Email services in general are highly reliant on DNS.
At the very least you will need an A/CNAME record pointing to your server's public IP, and an MX record so that other mail servers know where to deliver your emails. (applicable to every domain you intend using in your mail server)
Zhang has documented all the DNS information here: https://docs.iredmail.org/setup.dns.html
If you are still experiencing difficulty then let us know how/what you've done so far and where you're getting stuck.

If you are doing a test system at home that does not intend to send/receive over the internet, then you can create the DNS zone(s) on your home DNS server

6

Re: Recipient address rejected: User unknown;

What is not clear for me. If I sent an email to postmaster@virtualdomain.com from a local exchange server the email successfully arrive into iredmail mail box, but if II sent an email another user in the same virtual domain user what I have created before in iredmail it doesn't  receive email from exchange.

Jun 12 15:19:13 mx postfix/postscreen[3649]: CONNECT from [10.0.249.42]:48579 to [10.15.0.4]:25
Jun 12 15:19:13 mx postfix/postscreen[3649]: WHITELISTED [10.0.249.42]:48579
Jun 12 15:19:13 mx postfix/smtpd[3650]: connect from unknown[10.0.249.42]
Jun 12 15:19:13 mx postfix/smtpd[3650]: Anonymous TLS connection established from unknown[10.0.249.42]: TLSv1.2 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)
Jun 12 15:19:13 mx postfix/smtpd[3650]: 49k1XK5s53zG0: client=unknown[10.0.249.42]
Jun 12 15:19:13 mx postfix/cleanup[3656]: 49k1XK5s53zG0: message-id=<301c47e6d6d64d49a2f8ee0013cd01e9@birosag.hu>
Jun 12 15:19:13 mx postfix/qmgr[1811]: 49k1XK5s53zG0: from=<sandorsz@birosag.hu>, size=4316, nrcpt=1 (queue active)
Jun 12 15:19:13 mx postfix/smtpd[3650]: disconnect from unknown[10.0.249.42] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7
Jun 12 15:19:13 mx clamd[2367]: SelfCheck: Database status OK.
Jun 12 15:19:19 mx postfix/10025/smtpd[3668]: connect from mx.bkt.justice.hu[127.0.0.1]
Jun 12 15:19:19 mx postfix/10025/smtpd[3668]: 49k1XR1qZHzG1: client=mx.bkt.justice.hu[127.0.0.1]
Jun 12 15:19:19 mx postfix/cleanup[3656]: 49k1XR1qZHzG1: message-id=<301c47e6d6d64d49a2f8ee0013cd01e9@birosag.hu>
Jun 12 15:19:19 mx postfix/qmgr[1811]: 49k1XR1qZHzG1: from=<sandorsz@birosag.hu>, size=4790, nrcpt=1 (queue active)
Jun 12 15:19:19 mx postfix/10025/smtpd[3668]: disconnect from mx.bkt.justice.hu[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Jun 12 15:19:19 mx amavis[2291]: (02291-01) Passed CLEAN {RelayedInbound}, [10.0.249.42]:48579 ESMTP/ESMTP <sandorsz@birosag.hu> -> <postmaster@10.15.0.4>, (), Queue-ID: 49k1XK5s53zG0, Message-ID: <301c47e6d6d64d49a2f8ee0013cd01e9@birosag.hu>, mail_id: Yaza9aZeyBHr, b: 1cypgEcCs, Hits: -0.999, size: 4316, queued_as: 49k1XR1qZHzG1, Subject: "teszt II", From: <sandorsz@birosag.hu>, helo=levelezes.birosag.hu, Tests: [ALL_TRUSTED=-1,HTML_MESSAGE=0.001], autolearn=ham autolearn_force=no, autolearnscore=0.001, 5401 ms
Jun 12 15:19:19 mx amavis[2291]: (02291-01) Passed CLEAN, <sandorsz@birosag.hu> -> <postmaster@10.15.0.4>, Hits: -0.999, tag=2, tag2=6.2, kill=6.9, queued_as: 49k1XR1qZHzG1, L/0/0/0
Jun 12 15:19:19 mx postfix/amavis/smtp[3661]: 49k1XK5s53zG0: to=<postmaster@10.15.0.4>, relay=127.0.0.1[127.0.0.1]:10024, delay=5.6, delays=0.09/0.04/0.02/5.4, 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 49k1XR1qZHzG1)
Jun 12 15:19:19 mx postfix/qmgr[1811]: 49k1XK5s53zG0: removed
Jun 12 15:19:19 mx postfix/cleanup[3656]: 49k1XR2JFxzG0: message-id=<301c47e6d6d64d49a2f8ee0013cd01e9@birosag.hu>
Jun 12 15:19:19 mx postfix/qmgr[1811]: 49k1XR2JFxzG0: from=<sandorsz@birosag.hu>, size=4929, nrcpt=1 (queue active)
Jun 12 15:19:19 mx postfix/local[3669]: 49k1XR1qZHzG1: to=<postmaster@[10.15.0.4]>, orig_to=<postmaster@10.15.0.4>, relay=local, delay=0.08, delays=0.01/0.04/0/0.02, dsn=2.0.0, status=sent (forwarded as 49k1XR2JFxzG0)
Jun 12 15:19:19 mx postfix/qmgr[1811]: 49k1XR1qZHzG1: removed
Jun 12 15:19:19 mx postfix/pipe[3670]: 49k1XR2JFxzG0: to=<postmaster@levelezes.bkt.justice.hu>, orig_to=<postmaster@10.15.0.4>, relay=dovecot, delay=0.05, delays=0/0.02/0/0.03, dsn=2.0.0, status=sent (delivered via dovecot service)
Jun 12 15:19:19 mx postfix/qmgr[1811]: 49k1XR2JFxzG0: removed

But to another user:

Jun 12 15:21:11 mx postfix/postscreen[3709]: CONNECT from [10.0.249.42]:9866 to [10.15.0.4]:25
Jun 12 15:21:11 mx postfix/postscreen[3709]: WHITELISTED [10.0.249.42]:9866
Jun 12 15:21:11 mx postfix/smtpd[3710]: connect from unknown[10.0.249.42]
Jun 12 15:21:11 mx postfix/smtpd[3710]: Anonymous TLS connection established from unknown[10.0.249.42]: TLSv1.2 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)
Jun 12 15:21:11 mx postfix/smtpd[3710]: NOQUEUE: reject: RCPT from unknown[10.0.249.42]: 550 5.1.1 <bkthelpdesk@10.15.0.4>: Recipient address rejected: User unknown; from=<sandorsz@birosag.hu> to=<bkthelpdesk@10.15.0.4> proto=ESMTP helo=<levelezes.birosag.hu>
Jun 12 15:21:11 mx postfix/smtpd[3710]: disconnect from unknown[10.0.249.42] ehlo=2 starttls=1 mail=1 rcpt=0/1 quit=1 commands=5/6

Thank You!

7

Re: Recipient address rejected: User unknown;

why is there a requirement to send to addresses@ipaddress? can't you just give it a proper domain name? even if it's something on your local network, eg user@birosag.local
If you are already running exchange on your premises then you should have Microsoft DNS server in place, since Exchange cannot run without a Microsoft DNS server