I am trying to make my Kali Linux as a router to connect to Internet from an ethernet cable attached through my phone hotspot using USB tethering.
The topology is as follows:
Client -> Switch -> (eth0) Kali Linux (usb0) -> Mobile Hotspot (USB Tethering)
I have attempted the steps from this link (https://linoxide.com/ip-forwarding-connecting-private-interface-internet/) but our client is unable to access internet and ping the usb0 interface.
From Kali Linux, I am able to perform "ping -I eth0 8.8.8.8" and "ping -I usb0 8.8.8.8" sucessfully so I know the interfaces are able to access internet on their own.
What I have tried also was:
- Enable IP forwarding from eth0 as input and usb0 as output
- Attempted NAT masquerading
- lnxrouter tool (https://github.com/garywill/linux-router)
- Implemented a default route that goes out from the usb0 IP as the gateway in the kernel routing table.