2 complete networks  on one centos box

Posted on 2010-11-08
Last Modified: 2012-05-10
This is my third question to try to solve my issues, hope this one is clear and accurate.

I have 2 complete networks on my centos 5 box.




What I want is anything coming in on eth0 goes out on eth0 and the same for eth1.

I dont care if its static routes, iptables or whatever... I just want whatever coming in on eth0 goes out on eth0 and whatever comes in on eth1 goes out on eth1.

I have ssh/sftp users coming in on eth0 ( and they need to go out that same link (higher speed connection)

I have internal people using eth1 ( as their proxy server, and they need to go out on eth0 (so when people are downloading/uploading on eth1 internet is not slow for LAN users.


Question by:savone
  • 3
LVL 29

Expert Comment

by:Michael W
ID: 34086959
CentOS (and Linux for that matter) won't be able to do this by conventional means as for what you are asking for is considered a static NAT translation and routing table nightmare. Your best bet will be to look at using Shorewall Firewall/Router and deploying its Multiple Internet Connection Support.

Shorewall and Multiple Internet Connections

I have not set up such a routing layout, so this is where my help ends on this type of configuration.
LVL 29

Expert Comment

by:Michael W
ID: 34086986
This alternative configuration might work in a limited fashion.

How to setup multi-homing network
LVL 29

Accepted Solution

Michael W earned 500 total points
ID: 34087413
Source routing

Using advanced routing to control traffic across your interfaces
LVL 23

Author Closing Comment

ID: 34098390
Actually found a better tutorial here:

but you lead me to the promise land, thanks!

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