I would like to explaine how to troubleshoot the Fortigate Unit configured by Transparent Mode in step by step this time. Let's assume, you have one Fortigate Unit that configured as Transparent Mode. But devices from Internal/Private Network unable to access Internet/Public Network through your Fortigate Unit. OK. Let's troubleshoot with following steps, 1) Check the physical network connections between the network and the FortiGate unit, and between the FortiGate unit and the Internet. 2) Check the router and ISP-supplied equipment to make sure it is operating correctly. 3) Verify that you can connect to the internal interface by connecting to the management IP address of the FortiGate unit from the Internal network. From the internal network, attempt to ping the management IP address. If you cannot connect to the internal interface, verify the IP configuration of the PC and make sure the cables are connected and all switches and other devices on the network are powered on a
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