Question Outgoing Mail Control Anamoly

[Hangover2]

Server operating system version

Debian 11

Plesk version and microupdate number

Plesk Obsidian 18.0.70 Update #1

Hello,

We are currently facing a strange anomaly with the outgoing mail control. The system is configured to restrict:
- 60 emails per hour per mailbox
- 180 emails per hour at the domain level
- 240 emails per hour at the subscription level

Despite these settings, one client was able to bypass the 60-email limit per mailbox and managed to send 240 emails until the subscription-level limit was triggered.

The client used Outlook with SMTP authentication and many CC recipients. However, the email account’s statistics show 0 messages sent during the affected hour. The messages are only reflected in the domain-level statistics (showing 240/180!) and at the subscription level (240/240). Server logs show no anomalies, and the outgoing mail checks consistently return: py-limit-out: stderr: PASS till the subscription limit is reached.

The “Count the number of recipients instead of messages” setting is active. We have not been able to reproduce the issue with a test email account.

One notable detail is that the domain was recently moved using the “Create a new subscription” option.

Any insights or suggestions on what could be causing this behavior would be greatly appreciated.

Thanks in advance!

 

[Hangover2]

We have investigated the issue further, as additional problems with mailboxes under the affected client domain have continued to emerge.

It is now evident that the Plesk feature for moving domains to other subscriptions—or creating a new subscription from an existing domain—is buggy when it comes to mail services.

We encountered the following long-standing issues:

• Corrupted maildirsize files for all mailboxes under the transferred domain.
  A quick fix is available here:
  Plesk Support: Mailbox full / Unable to send or sync emails
• Mail forwarding stopped working with the error: "You are not allowed to use sendmail utility."
  A workaround is described here:
  Plesk Forum: Sendmail utility not allowed
• Outgoing mail limits database issues after moving the domain:
  Plesk Forum: Outgoing limits DB after moving domain

Based on these findings, we believe the outgoing mail control was also affected by the misconfiguration caused during the domain transfer.

We recommend escalating this to the Plesk development team, as it seems appropriate for the bug reports section. This feature has caused significant disruption and is now on our internal blacklist.