Random source ip to work around rate limiting

prepare-network.sh

#!/bin/sh

set -e

IF=${IF:-eth0:avahi}

for i in $(seq 1 30); do
  ip addr add "169.254.75.$i/16" dev $IF scope link || true
done

iptables -t nat -F RANDSRC || iptables -t nat -N RANDSRC
iptables -t nat -D POSTROUTING -p tcp --dport 80 -j RANDSRC || true
iptables -t nat -I POSTROUTING -p tcp --dport 80 -j RANDSRC

ip=$(getent hosts loadbalancer.local | awk '{print $1}')
for i in $(seq 30 -1 2); do
  iptables -t nat -A RANDSRC -d "$ip" -m statistic --mode nth --every "$i" --packet 0 -j SNAT --to-source 169.254.75.$i
done