Yes you can!
As you said, it’s got everything to do with routing and you don’t know how to do that yet.
Now’s a great time to learn!
If you’re on a time crunch, go ahead and use network namespaces under network manager to set up something like what you want as another user suggested.
If you have time to learn about the firewall and routing table rules, put on your wire rim sunglasses, pop a jungle cd in and crack open Linux Firewalls or some such book for nerds.
Yes that's called routing.
You don't bind it to a NIC, you specify the destinations you want forwarded to each interface. Your VPN connection is just another interface.
If you're looking for good docs, you may want to Google split tunnel vpn, and also bone up on your networking.
A few static routes should get you what you need
Everything you said is true, but I don't think it's the complete answer the OP would like.
For instance if somebody goes to Google, on the raw network, and on the VPN. They would correctly expect that traffic to take two different routes, and come from different IP addresses
And one doesn't even need two NICs, right.
Yes, that's what Gluetun is for. You create a Gluetun container and specify which containers should use it as the gateway in the compose file with:
network_mode: "service:gluetun"
Then you can open a shell in the container and run this to see if the container's IP is different from your own:
curl ifconfig.io
Make sure to try stopping the gluetun container and confirm your other containers lose network access.
There are plenty of guides about this if you search for "gluetun arr stack", like this random one I picked: https://www.smarthomebeginner.com/gluetun-docker-guide/
That has some steps outlining the basic gluetun configuration, how to put specific containers behind it, and test it.
Gluetun is for containers. OP is asking about routing.
I'm pretty sure OP is asking about forcing containers to use the VPN through gluetun.
"If I set up qBittorrent and the Arrs as Docker containers, can I use Gluetun to bind just them to the VPN?"
I think they are just misunderstanding what Gluetun is for.
It also exposes a proxy (and a tun), most things you want behind a vpn can use a proxy.
Not sure about the other stuff but qbittorent in its settings has a spot to specify which network interface to use. I always just select my vpns virtual interface. Never used surfshark so idk if itll work the same. Are the minecraft servers and everything you dont want on the VPN just LAN connections btw? I use Mullvad and it has a toggle to allow all the LAN connections through that you can turn on and off. Not sure if thats what u need tho.
Network namespaces!
ip netns exec namespace command
One namespace for surfshark, and anything you run in that namespace uses those rules
Network namespaces and policy based routing are black magic, IMO.
I've got a VPN set up on my router and separate VLANs set up for ordinary traffic and VPN traffic. A device doesn't need to support VPNs at all, I just connect it to the VPN VLAN and all its traffic goes over the VPN whether it likes it or not. I've got separate wifi SSIDs for each VLAN.
My desktop is connected to both VLANs with a network namespace set up for the VPN VLAN, so sudo vpn rtorrent runs rtorrent in the namespace that's connected to the VPN VLAN.
My setup is nice, but I wouldn't recommend it to anyone who doesn't want to learn quite a bit about networking.
Code dump for the curious?
Wait WHAT. Thank you.
Yes but why?
What's the VPN for?
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Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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