Sorry for the dumb question: how do I debug ip-forwarding?
My setup is as follows:
I have a Linux SoC connected via serial line to a Linux laptop
over that serial line I have a working PPP
sudo pppd updetatch connect 'chat -f chatscript' noauth nocrtscts local 192.168.8.1:192.168.8.2 /dev/ttyUSB0 115200
the laptop on the other end of the serial line has regular net connection (192.168.7.xxx)
I added a default route on SoC pointing to the remote PPP
ip route add default via 192.168.8.1
I enabled ip_forward
on laptop
echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward
This is not enough to have a working network though.
In order to reach the Internet I should enable NAT on laptop, but this is not my primary concern.
I checked ip-tables
on laptop and they all show
`Chain [INPUT/FORWARD/PUTPUT] (policy ACCEPT 0 packets, 0 bytes)`
My real problem is I would need to route form SoC to some other machine sitting om my regular LAN (192.168.7.0/24
).
I assume I need to add some sort of static route as addresses in 182.168.x.y
are not routable by default.
I am stuck here as I didn't find a way to ip route add ...
to make it working.
I am able to ping from SoC to Laptop and vice-versa, but nothing beyond that.
What should I add?