VPN IPSEC - Stabilized tunnel communication falls

Hi Birules 

Are you facing any issue in IPsec communication?

Is there any NAT device in between?

As per the logs its invalid SPI from the remote end, is tunnel configured between two Sophos device or different device at the remote end?

Can you share logs using below command from XG console > Advanced Shell?

service strongswan:debug -ds nosync

Please capture the logs and execute the same command again to toggle or turn off the debug

Hello Keyur,

I managed to solve this problem, but I did not understand why!!

In my XG firewall I did not move anything, but in the remote firewall we removed the NAT TRANSVERSAL.

The strangest thing is that in this location (remote) There is no NAT device in the between.

Are they each on their own zones?  Is there a firewall rule allowing communication between the zone?  

Badrobot,

Yes... Even by Packet Capture shows the packet passing by the correct rule!
Tks