Threat shield


The configuration page of this module is available only in the new Server Manager.

The Threat shield blocks connections to and from malicious hosts, preventing attacks, service abuse, malware, and other cybercrime activities using IP blacklists. It also blocks DNS requests for malicious domains using DNS blacklists. The package can be installed both on firewalls and on machines without a red interface, like mail servers or PBXs.


IP blacklist and DNS blacklist can be enabled and configured on the corresponding pages in the menu. Their configuration is almost identical.

First, set the Download URL for the blacklists. After setting the URL, the administrator can choose which blacklist categories should be enabled. Each category can have a Confidence score between 0 and 10. Categories with a higher confidence are less prone to false positives.

Enabled categories will be automatically updated at regular intervals.

The download URL must contain a valid GIT repository. Administrators can choose a public repository or subscribe to a commercial service. If the machine has a Community or an Enterprise subscription, the access to the URL will be authenticated using system id and secret.

A popular free IP blacklist is Firehol. Experienced administrators can also setup their own IP blacklist server.

An example of DNS blacklist is available at dns-community-blacklist.


If Web proxy is enabled, in any mode, DNS blacklist will not work for proxied hosts.


In case of a false positive, an IP address or a CIDR subnet can be added to the local Whitelist. If the firewall module is installed, the whitelist will also accept host and CIDR firewall objects.

Hosts should be added to the whitelist only for a limited period of time. As a best practice, when a false positive is found, please report it to the blacklist maintainer.

Incident response

The Analysis page displays most recent attacks and DNS requests which can be easily filtered by source, destination and other attributes. Using the Check IP address or domain section, administrators can also check if a given IP or domain has been blacklisted by enabled categories.

For advanced log analysis with regular expressions support, use the Logs page.


The Dashboard page provides an overview on current status of IP and DNS blacklists and displays graphical information about blocked attacks.

IP blacklist dashboard provides:

  • Today’s total number of threats blocked
  • Today’s most blocked source hosts
  • Today’s most blocked destination hosts

DNS blacklist dashboard provides:

  • Today’s total number of threats blocked
  • Today’s total number of DNS requests
  • Today’s threats percentage
  • Top clients performing most DNS requests
  • Top blocked domains
  • Top requested domains