Related

Tool [NEW] Bandwidth Pricing Calculator Tool
How to unlocked droplet network access locked by Digital Ocean? Question Question
Why are snapshots so slow Question Question

Question

Firewall - Traffic Routing

Posted June 14, 2016 4.2k views
UbuntuSecurityDigitalOceanNetworkingFirewall

I have 2 droplets. Lets say FWserver and APPserver. I want to make sure that all inbound and outbound traffic in my private networking is going via FWserver. on FWserver,eth0 is connected to internet (ip 139.59.x.x) and eth1 is connected internally to private network (10.139.y.y).

on FWserver, I did the following
echo 1 > /proc/sys/net/ipv4/ip_forward
route add -net 10.0.0.0./16 dev eth0
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

From APPserver

I am able to ping and connect to private networking ip 10.139.y.y
However I am unable to reach the public ip 139.59.x.x

I guess that is the first step before I can connect to internet from APPserver via FWsever

Please help. this is urgent for me to setup my private networking

thanks
UK

Add a comment
umakot
By:
umakot
Add a comment
1 comment

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

×
1 answer
brass June 16, 2016

first step is to make FWserver forwarding persistent

echo net.ipv4.ip_forward = 1 >> /etc/sysctl.conf
sysctl -p

second is to make sure all iptables rules are in the rule base

iptables -A PREROUTING -d 139.59.x.x -p tcp -j DNAT --to-destination 10.139.y.y
then your masquerade rule
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

with those rules you should be able to ping default gateway from your 10.139.y.y address, if the APPserver nics are configured correctly to interface with the eth1 on FWserver.

Reply Report
Submit an Answer

Related

Looking for something else?

Ask a new question Search for more help