- Plesk 12.5 for Linux
- Plesk Onyx for Linux
CBL lists the server in their Blacklist constantly.
There is no trace of spam in the logfiles, nor captured by Outbound Antispam Control.
The following error can be found in
CONFIG_TEXT: 54 Service unavailable; Client host [example.com] blocked by cbl.abuseat.org; Blocked - see http://www.abuseat.org/lookup.cgi?ip=203.0.113.2 (in reply to RCPT TO command)
The following SQL query shows bounce values for any domain on the server:
MYSQL_LIN: select domains.name, Parameters.value from domains, Parameters, DomainServices where domains.id = DomainServices.dom_id and DomainServices.parameters_id = Parameters.id and Parameters.parameter = 'nonexist_mail' and Parameters.value <> 'reject';
| name | value |
| example.com | bounce|
One or more domains are configured to bounce email on rejection. According to the CBL < http://www.abuseat.org/qmailhelp.html > site, there a high probability that the server IP is being listed due to a bounce to an external server marking it as spam.
To avoid this, apply the following steps:
1. Change settings for the domains listed in the SQL query, so they meet CBL best practices, by enabling the reject flag for non-existent users:
Subscriptions > example.com > Mail Settings
2. Disable the option for customers either by disabling the "Ability to change mail settings" flag in:
Subscriptions > example.com > Permissions > Show more available permissions (Note that this step will lock the subscription)
Or by hiding the control for rejection messages for non-existent mail globally in Tools & Settings > Interface Management > Interface Control Visibility > Hide controls for rejection messages for non-existent mail addresses
3. Contact CBL to unban your host.