How to setup NAT overload on iptables?

Question

iptables

Please tell me how to set up dynamic NAT Overload using iptables on routers (image below)

Now there is no idea how it works, I would be grateful for an explanation on the fingers, specifically on this example.

Answer 1

Well, you need to have a conscience: https://bitrainbow.wordpress.com/2015/02/25/%D1%81...
The pat (nat overload) itself is configured with one command

iptables -A POSTROUTING -s 192.168.N.0/24 -o eth1 -j SNAT --to-source 10.N.0.1

for the first network and the second command

iptables -A POSTROUTING -s 192.168.N+1.0/24 -o eth1 -j SNAT --to-source 10.N.0.2

for the second.
What's difficult?