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I am on a LAN at work, connected with an ethernet cable.

Now, when I plug in my 3G Network Adapter (dongle), the Ethernet connection still has preference over the 3G connection.

Now I want connect certain applications via the 3G only, but it chooses the ethernet LAN gateway as the gateway to the internet.

So lets say I want to configure the proxy settings in Firefox to connect via the 3G, how do I do that? What address do I use and what port?


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I think you would have less trouble the other way around. That is, performing the tasks you want to be performed through your mobile connection on your phone, and controlling your phone from the computer, through the USB port. – Ariane Aug 23 '13 at 9:04

U can change default gateway

sudo route add default gw <gateway ip>

find gateway ip of 3g connection from ifconfig

This makes all applications to use 3g connection to connect to internet. I don't think there is a tool on linux that enables to map applications to network interfaces to connect to internet. I hope there should be a warm welcome to such a tool.

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cool thank you. If I add the route, won't that route be overwritten by ethernet route which is default?. Also, how would I know which port to use? Cant ping port 80 on the gateway address. – DextrousDave Aug 23 '13 at 8:47
also, this is in Windows... – DextrousDave Aug 23 '13 at 8:47
But routing all connections via the 3G this way is just as good plugging the ethernet out...I still want to use the ethernet, I only want certain apps(like utorrent) to use the 3G connection – DextrousDave Aug 23 '13 at 8:49
@DextrousDave yes it will be over written till u disconnect the 3g modem or restart. on windows simply set lan ip4 properties to static and dont give default gw but u have to reset lan gateway once u disconnect the modem – neckTwi Aug 23 '13 at 8:52
If u unplug the ethernet u loose access to computers on network – neckTwi Aug 23 '13 at 8:54

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