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@thomaspatzke
Created January 19, 2016 22:46
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Shell script to quickly switch between real Internet connection (NAT) and simulated (INetSim)
#!/bin/bash
case "$1" in
router)
sysctl -w net.ipv4.ip_forward=1
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
systemctl start dnsmasq.service
;;
router-stop)
sysctl -w net.ipv4.ip_forward=0
iptables -t nat -D POSTROUTING -o eth0 -j MASQUERADE
systemctl stop dnsmasq.service
;;
inetsim)
iptables -t nat -A PREROUTING -i eth1 -j REDIRECT
inetsim
iptables -t nat -D PREROUTING -i eth1 -j REDIRECT
;;
*)
echo "Usage: $0 {router|router-stop|inetsim}"
;;
esac
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