relay.sh

#!/bin/bash

# where plex network is the zt-network-id plex is connected to
plexnetwork=XXXX
plexserver=172.30.1.6
plexport=32400

# install updates
DEBIAN_FRONTEND=noninteractive
apt update
apt dist-upgrade -y
apt install iptables-persistent iftop -y

# install zerotier
curl -s https://install.zerotier.com | sudo bash

#
if [ -x $(which zerotier-cli) ]; then
  zerotier-cli join $plexnetwork
fi

# setup iptables routing
echo net.ipv4.ip_forward=1 >> /etc/sysctl.conf

iptables -t nat -A PREROUTING -p tcp --dport $plexport -j DNAT --to-destination $plexserver:$plexport
iptables -t nat -A OUTPUT -p tcp -m tcp --dport $plexport -j DNAT --to-destination $plexserver:$plexport
iptables -t nat -A POSTROUTING -j MASQUERADE

netfilter-persistent save