Dear Team,
How to fixt this error -
The L2TP connection attempt failed because the security layer encountered a processing error during the initial negotiations.
FYI - I have configured L2TP IPsec vpn in Fortigate Firewall, I am getting error while connecting VPN.
How to resolve it and what are the troubleshooting stpes for it.
Thank you in advanced
Hi Umesh,
Please check the cookbook for some guidance Cookbook | FortiGate / FortiOS 6.2.0 | Fortinet Documentation Library
Best regards,
Jin
Hi Jin,
I would like to tell you that I was able to access L2tp vpn from my windows machine and after 1 hour I was trying to connect again to access the network. then I am getting error.
even I have gone through Fortigate cook but issue could not be resolve till now.
Could you please tell me what can be possible issue .
thank you.
Hi,
The first post didnt mention that you connected l2tp successfully, and therefore cookbook reference for setting up the right configs were provided. Now that subsequent attempts are resulting in error, this could be from the windows machine or the path but configs on FortiGate is assumed fine since you connected earlier. On FortiGate, you can perform troubleshooting using the below commands when l2tp connections are attempted,
diagnose debug application ike -1
diagnose debug application l2tp -1
diagnose debug enable
Please see https://docs.fortinet.com/document/fortigate/6.0.0/Handbook/269357/troubleshooting-l2tp-and-ipsec
Best regards,
Jin
Tips to fix-
1. Check Your Regular Network Connection.
2. Make Sure the VPN Login Credentials Is Correct.
3. Try a Different VPN Server.
4. Reinstall VPN Software.
5. Disable IPv6 Protocol.
6. Troubleshoot VPN Not Connecting Windows 10 by Temporarily Disabling Firewall.
Regards,
Rachel Gomez
Regards,
Rachel Gomez
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