• Debian 11 is approaching its end-of-life (vendor EOL date - August 31, 2026). Plesk Obsidian 18.0.80 will be the last release to support it.
    If you are running Plesk Obsidian on Debian 11, we recommend you upgrade those servers to Debian 12 using our dist-upgrade tool.
  • We plan to deprecate and remove the support for XML RPC protocol versions earlier than 1.6.9.1 in Plesk Obsidian 18.0.82. We strongly recommend that you update all existing integrations using earlier versions of the XML RPC protocol to comply with the version 1.6.9.1 specification.

[greylisting] mails are much longer rejected than configured

Lars

New Pleskian
(Panel-Version 11.5.30 Update #51 on Ubuntu 12.04.5 LTS)

We encounter the situation that the 'grey_listing' plugin sometimes reject a mails much longer than expected.
Last time this happens the mail was locally accepted over thirty hours later. The log file is not showing anything unusual:

Jan 7 11:11:11 server greylisting filter[11359]: Starting greylisting filter...
Jan 7 11:11:11 server /usr/lib/plesk-9.0/psa-pc-remote[646]: handlers_stderr: DEFER
Jan 7 11:11:11 server /usr/lib/plesk-9.0/psa-pc-remote[646]: DEFER during call 'grey' handler
Jan 7 11:11:11 server /usr/lib/plesk-9.0/psa-pc-remote[646]: Message aborted.

Going through the logs for this mentioned last case I figured out that the sender was using Microsoft's Mail Service "outlook.com". This service has a large amount of servers (IPs) to send remote mails. In our case it was always a different IP for every single (rejected) delivery attempt. And then thirty hours after the first attempt, as an "known" Remote-IP was trying again, the mail was locally accepted.

I don't know what parameters 'grey_listing' is using to identify delivery attempts but the remote IP might be not such a good idea? Any idea what to do to avoid those massive delays?
 
Back
Top