Issue mail forwarding loop for

[Sebastian Braun]

Hello together,

we have a problem with our new mailserver (mail.example.com), which we did set up last week.

Every email which is sent to a redirected email-adress is answered by the following error from
Mail Delivery System <MAILER-DAEMON@mail.example.com>

We cannot find any mistake there.


---
This is the mail system at host mail.example.com.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

<test5@example.com>: mail forwarding loop for test5@example.com
---
Mailboxes:
Dropbox - Screenshot 2018-09-10 14.12.53.png

Settings:
Dropbox - Screenshot 2018-09-10 14.14.34.png

Maillog:

./maillog:59112:Sep 10 15:31:21 mail postfix/pipe[14291]: EB55A1017A7: to=<test5@example.com>, relay=plesk_virtual, delay=0.28, delays=0.08/0/0/0.2, dsn=2.0.0, status=sent (delivered via plesk_virtual service)
./maillog:59332:Sep 10 15:33:46 mail postfix/pipe[14718]: 8C9B510144F: to=<test5@example.com>, relay=plesk_virtual, delay=0.08, delays=0.08/0/0/0, dsn=5.4.6, status=bounced (mail forwarding loop for test5@example.com)​

I replaced our domain by example.com.
Does somebody know how to fix this?

 

[IgorG]

Please check this KB article Unable to forward email: mail forwarding loop

 

[Sebastian Braun]

Hi IgorG,
thank you for your answer, but I am not sure I have the same problem than the one described in the kb. The mails which are responded by the Mailer Daemon are forwarded and arrive in the mailbox of the recipient, so the forwarding itself is working.

My console says:

root@mail:~# ls -lahp /usr/sbin/sendmail
lrwxrwxrwx 1 root root 43 Sep 4 15:19 /usr/sbin/sendmail -> /usr/lib/plesk-9.0/postfix-sendmail-wrapper
​

Is that right or wrong?

 

[IgorG]

For me:

[root@ppu17-8 ~]# ls -lahp /usr/sbin/sendmail
lrwxrwxrwx 1 root root 21 Sep 11 10:12 /usr/sbin/sendmail -> /etc/alternatives/mta

[root@ppu17-8 ~]# ls -lahp /etc/alternatives/mta
lrwxrwxrwx 1 root root 43 Sep 11 10:12 /etc/alternatives/mta -> /usr/lib64/plesk-9.0/qmail-sendmail-wrapper

[root@ppu17-8 ~]# plesk version
Product version: Plesk Onyx 17.8.11 Update #20
Update date: 2018/09/11 10:12
Build date: 2018/09/06 15:47
OS version: CentOS 7.2.1511

 

[Sebastian Braun]

Hi Igor,
thank your for your quick answer, but I still do not know I have to change this symlink or not - and why?
Mails from outside are delivered and forwarded correctly, but with error warning from MAILER DAEMON.

root@mail:~# plesk version
Product version: Plesk Onyx 17.8.11 Update #19
Update date: 2018/09/04 15:20
Build date: 2018/08/31 07:46
OS version: Ubuntu 16.04
Revision: 382b33f84a88242d787d34ac0b4da799f4a90182
Architecture: 64-bit
Wrapper version: 1.2

root@mail:~# ls -lahp /etc/alternatives/mta
ls: cannot access '/etc/alternatives/mta': No such file or directory
​

So this middle-symlink is not existing in my system.

 

[IgorG]

Have you tried to repair mail server settings with

# plesk repair mail

at least?

 

[Sebastian Braun]

root@mail:~# plesk repair mail

Repairing the mail server configuration

Reconfigure all domains and mailboxes? [Y/n] y
Reconfiguring all domains and mailboxes ......................... [OK]

Error messages: 0; Warnings: 0; Errors resolved: 0
​

But Mail Delivery System is still answering the mail with the known error message.