Specific IP - No Internet access

[ThePro]

This is an existing installation (didn’t configure it myself originally). For some reason a specific IP doesn’t have Internet access. I have tried it with 2 different computers. As soon as I activate that IP the computer loses Internet connection (it doesn’t loose access to the local network). I don’t see any special rules or routes that could be causing the issue. Any ideas?

[Toshi_Esumi]

If other device within the same subnet/on the same interface work but those, and you don't see anything obvious in the config blocking traffic from those specific devices, you need to run "flow debug" to see why it's dropped or blocked.

[TecnetRuss]

Try this: open a CLI console and type:

show | grep -f x.x.x.x

(where x.x.x.x is the IP address that is not working on the LAN)

If this IP address is defined anywhere in your FortiGate's configuration this will tell you where.  For example, the IP could be used in a bad Policy Route that is sending traffic from that IP out a bad gateway, or you could find that IP misconfigured in an IP Pool.

If this matches an address object (e.g. "ComputerX"), run the command again for hits against the object name (e.g. show | grep -f ComputerX).

Russ