SoftEther VPN User Forum

First of all thanks for this great piece of software.

When evaluating it, I found some traffic denied on my firewall that were surprising me. I run the server version on a linux and on a win7 and both seems to act the same way.
The traffic is mostly IP proto 52 and UDP/5004. Sometimes I also found http(s). This trafic is always trying to reach some server belonoging to the Japan Amazon IP range. My config is not using Dyndns, is not configure for Azure or as VPN gate. Logically it should not initiate any external connection.

Could someone explain this traffic?

Thanks in advance

VPN server uses NAT traversal service to manage UDP hole punching at default setting.
If you don't want to use this feature, please edit config line 'DisableNatTraversal'.

Thanks for your quick reply. I will check this tomorrow and let the forum knows about the result.

I did check this new setting and this outgoing traffic is still there. I am not sure but it seems that is it happenning only when I start or stop the server.

did you run wireshark ?
take a trace - enough to have this traffic -
Then analyze it using https://www.networktimeout.com/

Maybe you will find something.

Let us know !

I have had the exact strange behavior, but for me disabling NAT Traversal ('DisableNatTraversal') did work..
Thanks!

-Joe42