Need forwarding to Telford Internal IP Address – 10.10.1.1
Fixed Internet IP Address – 1.1.1.1

Ports 40000, 41000, 42000, 43000, 44000, 45000, & 46000 need forwarding to 10.10.1.1

Configuration to be Done.

Need to create a Ethernet Subinterface on the VM :

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]
DEVICE=eth1:3
BOOTPROTO=static
ONBOOT=yes
HWADDR=00:0c:29:fa:da:13
IPADDR=1.1.1.1
NETMASK=255.255.255.0
NETWORK=1.1.1.254
BROADCAST=1.1.1.253
Bring Interface UP :

sudo ifup eth1:3

To View a list of rules with the NAT table :

sudo iptables -vnL -t nat –line-numbers

Need to complete PREROUTING chain in order to DNAT these ports from WAN to destination LAN address :

sudo iptables -t nat -I PREROUTING 1 -d 1.1.1.1 -p tcp –dport 40000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 2 -d 1.1.1.1 -p tcp –dport 41000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 3 -d 1.1.1.1 -p tcp –dport 42000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 4 -d 1.1.1.1 -p tcp –dport 43000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 5 -d 1.1.1.1 -p tcp –dport 44000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 6 -d 1.1.1.1 -p tcp –dport 45000 -j DNAT –to 10.10.1.1
sudo iptables -t nat -I PREROUTING 7 -d 1.1.1.1 -p tcp –dport 46000 -j DNAT –to 10.10.1.1

To summarize this as one rule :

sudo iptables -t nat -I PREROUTING 18 -d 85.234.86.115 -p tcp -m multiport –dport 40000,41000,42000,43000,44000,45000,46000 -j DNAT –to 10.10.1.1

Need to complete POSTROUTING chain in order to SNAT these ports from LAN address to destination Subinterface : :

sudo iptables -t nat -I POSTROUTING 20 -o eth1:3 -s 10.10.1.1 -p tcp -m multiport –dports 40000,41000,42000,43000,44000,45000,46000 -j SNAT –to 1.1.1.1

To Delete a Chain Rule

sudo iptables -t nat -D POSTROUTING 20
sudo iptables -t nat -D PREROUTING 20

Troubleshooting Diagnostics Testing :

From the Internet :

telnet 85.234.86.115 40000

B00m.