How To Avoid Syncing Through Mobile Data

[cheesecake]

I plan to sync sensible data with BTsync exclusively on my local private network between a Windows PC, an Android mobile phone and an Android tablet. Under no circumstances a sync through mobile data should be possible. On all devices the newest version of BTsync is installed.

 

The devices are configured as follows:

Windows PC: "Use relay server", "Use tracker server" and "Search DHT network" are disabled. "Search LAN" is enabled, no predefined hosts.

Android mobile phone: WiFi is disabled, mobile data is enabled. In BTsync "Use mobile data" is enabled. The objective is, that the phone can never sync folders with BTsync through mobile data.

Android tablet: WiFi is disabled, tablet is not able to use mobile data.

 

I added some files on the PC to the sync folder and deleted some other. Then I tried to sync the changes on the mobile phone through mobile data, but I did not succeed because of the settings of BTsync on the PC. That's what I expected.

 

I now turned WiFi on on the tablet. As expected, BTsync synced the changes I made on the PC through my local network. Well done, but oops: When checking the sync folder on the mobile phone again, it is unexpectedly in sync with the other devices. There must have taken place a synchronsisation between the tablet and the mobile phone. That is exactly not what I want: Syncing the folder through mobile data.

 

Did I do something wrong in configuring BTsync on the devices? Or does the mobile BTsync app by default uses tracker server, relay server and search the DHT network? In contrast to the PC app I can not find options to disable/enable these settings.

 

Any help?

[RomanZ]

@cheesecake,

 

Indeed, mobile devices are using tracker and relay server by default. Even more, when peers are communicating each other - they also share the information on IPs and port of other peers with the same shares.

 

For example - in your environment PC has no access to tracker and relay, while tablet has. Tablet can contact your cellphone (which is not in LAN) over internet. And, Tablet will let phone know the IP:port of your PC, so - phone can talk to PC from internet - and PC will response.

 

So, to support the "LAN only" setup all the peers must avoid using tracker and relay server, which is not possible for mobile phones currently. All I can advise for now is to put some false IPs (localhost, for example) to hosts file on your mobile devices if this is possible. Or just block certain IPs (again, if possible).

 

You need to prevent access to 3 locations: config.usyncapp.com, t.usyncapp.com, r.usyncapp.com.

[cheesecake]

@RomanZ,

 

Thank you for the clarification.

Are there plans to implement in the mobile apps the same options to enable/disable tracker, relay and DHT for each sync folder like in the desktop apps?

I think blocking or redirecting the IPs on mobile devices is not really an option.This would genenerally prevent btsync to sync some  folders over the internet and others only locally. Both should be possible.