- Firewall rules which were added manually in the server console using the utility
The extension Plesk Firewall is installed on a Plesk server. and enabled via Tools & Settings > Firewall > Enable Firewall Rules Management.
All custom firewall rules are replaced with the rules defined in Plesk Firewall in Tools & Settings > Firewall.
Go to Tools & Settings > Firewall.
Add custom rules as described in Plesk Administrator's Guide.