Symptoms
- Plesk Obisidian running on a Linux-based operating system
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Emails sent through a mailing list (mailman) to external mailboxes (Gmail, Outlook, Yahoo!, etc.) are not received
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The messages do not appear to be leaving the Plesk server and one of the following error messages appears in
/var/log/maillog:NOQUEUE: reject: RCPT from localhost[::1]: 454 4.7.1 [email protected]: Relay access denied;
[email protected] [email protected] proto=ESMTP helo=<mail.example.com>
NOQUEUE: reject: RCPT from localhost[127.0.0.1]: 554 5.7.1
Cause
The localhost IPv4 and IPv6 address ranges are not whitelisted within the mail server settings.
Resolution
Warning: To use mailing lists, you need to have localhost (IP ranges 127.0.0.0/8 and ::1/128) in the mail server's white list. However, to use outgoing mail control, you should not have localhost in the mail server white list. As a compromise, you can use mail forwarding on the mailbox instead of mailing lists.
The localhost IPv4 range 127.0.0.0/8 and IPv6 range ::1/128 must be added to the mail server white list in order for mailman to function as expected:
Warning: By applying the following solution, any set limits on outgoing mail will stop working and this is expected.
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Go to Tools & Settings > Mail Server Settings > White List
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Press Add Network > add
127.0.0.0/8to the IP address/mask field -
Press Add one more > enter
::1/128to the IP address/mask field -
Press OK
- The end result should appear as follows:
Mailman Limitations:
- By default, the Mailman web interface in Plesk is secured with a self-signed SSL/TLS certificate. It protects the connection but triggers a self-signed SSL/TLS certificate warning. You can safely ignore the warning when you access the Mailman web interface. At the moment, it is not possible to secure the Mailman web interface with a valid SSL/TLS certificate.
- At the moment, Mailman does not support ARC headers, therefore emails sent via Mailman cannot pass ARC checks. Some mail services (for example, Gmail) may treat such emails as unauthenticated.
- The operating system dist-upgrade (for example, from Debian 10 to Debian 11) requires manual actions to upgrade to Mailman 3