FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
Article Id 276105
Description This article describes troubleshooting steps if getting Duplicate IP message or IP conflict log.
Scope 7.0+.

If getting a Windows event notification that there is an IP conflict and the Mac address of that is matching with FortiGate then it may be related to IP Pool configuration.


If for example, an IP Conflict for is shown, then an IP Pool similar to this should exist:




Here disable the ARP Reply option and select ‘Ok’. Then a configuration should appear as shown below:




This should resolve the IP Conflict. With the ARP reply enabled, FortiGate responds to ARP requests which can cause IP conflict in the environment.