Download your favorite Linux distribution at LQ ISO.
Go Back > Forums > Linux Forums > Linux - Networking
User Name
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.


  Search this Thread
Old 08-03-2015, 12:40 AM   #1
LQ Newbie
Registered: Jul 2014
Posts: 11

Rep: Reputation: Disabled
Ubuntu router/fw - RDP across subnets

I have set up a Ubuntu 14.04 server as a router with 3 NICs - 1 for internet access, 2 for internal subnets - one a LAN, one a DMZ:
eth0: 23.x.x.1 - internet
eth1: - DMZ gw
eth2: - LAN gw

I have a windows server in the DMZ and I can ping it from a client on the 10.2.0.x subnet but when I try to RDP it denies the connection almost immediately (testing through telnet). I'm using all default settings in my before.rules file and have tried the following 2 ufw rules:

allow from any to
allow from any to port 3389

I also checked the ufw logs and didn't see any entries showing the source IP of the client I am running RDP from nor showing the destination IP or port 3389 of my destination server.

If ping can traverse the ubuntu router and i get a reply from the server, I would think RDP would work as long as I have 3389 open in ufw on the router. I'm using RDP from a windows 8 computer to access a windows 2012 server across the ubuntu router and its not the source or the destination systems, I already verified that. Can anyone offer any insight about what I need to do here? I'm stumped and have to be missing something.

Also, just for context, I'm not that great with networking and linux yet, this is all part of me trying to learn them both. Thanks in advance.

UPDATE: I can't access any services across subnets. I've tried DNS, SSH and RDP.

Last edited by raeif; 08-03-2015 at 07:34 PM.
Old 08-04-2015, 11:23 AM   #2
Slackware Contributor
Registered: May 2015
Distribution: Slackware
Posts: 1,904

Rep: Reputation: 1053Reputation: 1053Reputation: 1053Reputation: 1053Reputation: 1053Reputation: 1053Reputation: 1053Reputation: 1053
Did you enable ipv4 forwarding on the router?

Here is how to do it:

Last edited by mralk3; 08-04-2015 at 11:26 AM.



Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
how to configure linux virtual machine as router which communicate between 2 subnets krati_93 Linux - Networking 1 07-18-2014 03:24 PM
Ubuntu 12.04 LTS as router, two subnets and no communucation between them Chris9760 Linux - Networking 4 03-05-2014 07:39 AM
setting up subnets for home network with adsl router linuxmandrake Linux - Security 1 05-06-2009 02:04 PM
Two identical subnets and no physical router samylightfoot Linux - Networking 1 04-28-2009 07:38 AM
I need to setup a Linux router for my 2 public subnets drcoco Linux - Networking 4 05-17-2006 09:36 PM > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 06:08 PM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration