Ask Your Question

How to create bridge - 3G Internet and Ethernet Port (LAN) on a PC ?

asked 2014-03-29 06:19:10 -0500

dmm gravatar image

updated 2014-03-29 07:24:07 -0500

hi folks

here is my setup - I have a 4-port switch in the attic

I have a 3G internet dongle attached via USB to a PC lets call the PC "PC-net" the 3G internet dongle assigns itself as a gateway using a gateway IP address of - on PC-net.

i went into the network conections option in windows 7 this is what i do

I create the bridge by highlighting the 3G dongle connection and PC-net’s ethernet connection together and right click and choose “create bridge” when the bridge is created I statically assign the bridge an IP address of - so now PC-net has that address and when i connect the ethernet cable from PC-net into the 4-port switch i have 2 way flow (in/out) of internet through the ethernet ( lan ) port of PC-net

so that when connected to the switch via ethernet cable PC-net effectivelty shares its internet with all other PC’s connected to the switch - i can assign these other pcs static ip addresses - so theyre ok

preconditions - 1. i dont want to nor am i willing to buy a 3G router as i know its unnecessary and expensive 2. i want to be able to assign the client PCs their IP addresses manually in the range to

how do I achieve this in linux (Fedora in my case) - if i install fedora (or other linux) on PC-net - how do i achieve the above windows equivalent setup on linux - can i do it using GUI or do I need to use those scary iptables commands ? thanks

edit retag flag offensive close merge delete

1 Answer

Sort by » oldest newest most voted

answered 2014-04-01 23:22:26 -0500

billmcgonigle gravatar image

To just share the internet connection, that's built in, with a few clicks of the GUI (set up the 3G connection, then configure the LAN port for "Share this connection").

NetworkManager's bridge support is pretty new (it's finally happening) and might not do exactly what you want yet (though it might). Setting up a bridge in the text files is not bad and there are a hundred blogs that tell you how to do it.

The biggest reason to bridge from your requirments is to get the other machines at .125-.128. That's a particularly bad IP range for trying to do any subnets, as every subnet scheme will have a hole at 127 and 128.

Most people would just let NetworkManager automatically set up a routed network for them to use for the sharing - your use case is fine but has a couple of atypical wrinkles that keep it from fitting the most common cases.

edit flag offensive delete link more

Question Tools

1 follower


Asked: 2014-03-29 06:19:10 -0500

Seen: 11,094 times

Last updated: Apr 01 '14