The Log Forwarding feature in Palo Alto Networks firewalls allows administrators to perform automated actions based on logs. One of the actions that can be configured is to tag an IP address, which can then be used in conjunction with Dynamic Address Groups (DAG) to enforce security policies. By tagging the destination IP addresses of unwanted traffic, an administrator can dynamically update policies to block traffic to those destinations.
This method is particularly useful for responding quickly to detected threats by creating and enforcing a policy that blocks traffic to tagged destinations without the need for manual intervention or policy changes.For a detailed explanation, the Palo Alto Networks' "PAN-OS Administrator's Guide" provides information on log forwarding and automated actions.