Btsync Over The Internet...through Firewalls Etc.

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If I want to sync two servers, connected via the Internet, could someone please confirm the correct settings for 'listening port' and the NAT/uPnP setting?


Whilst there is a 'listening port' setting in the GUI, there does not seem to be a 'sending port'.

I am not sure about the effect of the NAT tickbox.


I would like to sync two servers over the Internet, lets say using TCP Port 6666. That way I can set up firewalls and routers to direct this tcp port to the desired servers at each end of the link.


Do I set both servers to 'listen' on port 6666? and turn off NAT?? Do they also 'send' on port 6666 if I do this??


Any information welcome.

Thank you.


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BTSync uses listening port for incoming UDP packets and TCP connections. When BTSync uses UDP - it uses the same port for outgoing data packets, but when it uses TCP - it has to pick a random outgoing port.


In your configuration (2 computers sitting behind NATs trying to talk over internet) the most simple setup is to enable UPnP on your NATs and make sure it is enabled in BTSyncs. 

If you do not trust UPnP or can't enable it - you can make a port forwarding. In this case you need NAT to forward exactly same port as configured as "Listening" to the PC where BTSync resides.



The listening port is used not only when using the tracker to find each other. In LAN discovery once PCs exchange data in Multicast packets - they will know each others listening port and connect to it. But you are right in the second part - if the Listening port is open in firewall (assuming this is stateful firewall) and mapped via NAT - BTSync should work fine.

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