Configuring Raspberry Pi as a router
From MyWiki
Enable Forwarding to Reach the Internet
Enable IPv4 forwarding sudo sysctl -w net.ipv4.ip_forward=1 1
sudo sysctl -w net.ipv4.ip_forward=1
Enable NAT sudo iptables -t nat -A POSTROUTING -j MASQUERADE 1
sudo iptables -t nat -A POSTROUTING -j MASQUERADE