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L2TP over IPsec

Dear All.


I have following quires which are as follows:


1. Does L2TP over IPsec VPN work without License. 

2. Without licensing I was configuring  L2TP over IPsec communication was not happing between initiator (Windows machine) and responder (Fortigate Firewall) even not able to connect responder.

3. After applying  license VPN was able to connect but communication was not happing from initiator to responder.

I had followed  below URL in order to configure -


Can anyone tell me what can be issue even after connecting vpn, communication was not happing.


thank you.






If the tunnel is up but traffic is not passing, you need to run debug flow:


di deb disable
di deb res
diagnose debug flow filter clear
di deb flow filter addr
di deb flow filter proto 1
diagnose debug flow show function-name enable
di deb flow show iprope en
diagnose debug console timestamp enable
diagnose debug flow trace start 500
diagnose debug enable




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