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I have an interesting issue with OpenVPN Ubuntu 12.04.

I've been running an OPenVPN box for some time now. Clients can connect with Linux, Windows and OSX no problem and it seems stable.

However I added another host to the network recently and it is not accessible over the VPN.

Some of the details are: LAN Gateway VPN Box: Bad Machine:

So basically I can ping, ssh, web browse e.t.c to any machine on the LAN apart from

When I'm in the office it is fine I can connect to all services on that machine no problem.

The only difference I see is:

  1. All other hosts use Ubuntu Desktop 12.04, this one uses Ubuntu Server Edition 12.04
  2. This box is a proper server (Dell PowerEdge 2850) the other hosts are just old desktops.

I'm leaning towards the issue being with the Ubuntu server box and not the vpn because I can access it inside the LAN but not inside the LAN over VPN where all other hosts are perfect.

I know it is using an unused IP Address and I've tried it on different ip addresses. Iptables is set to ACCEPT everything.

Our network consists of 2 patch panels, 2 switches sitting behind a Cisco 800 series Router.

Anyone got any ideas? I cant understand why it blocks everything on VPN connections, If done this lots of times without any problem.

share|improve this question
What address range(s) are you using for your O'VPN pool, are they being NATted by the onsite O'VPN server, and does the .48 box have a route back to the resulting pool (or is its default gateway set to a box that does)? – MadHatter Jan 3 '13 at 9:23
After MadHatter questions are replied, 1) use tcmdump on that "bad" machine to see if you receive packets (if not, another hosts receive them). 2) Check its routes and netmask and default gateway, to see if the reply will indeed go toward the right machine (the OpenVPN box) – Olivier Dulac Jan 3 '13 at 13:26
iptables is probably the real source of the problem... Try another time to figure out if it's correct and nothing is missing. – Olivier Dulac Jan 3 '13 at 13:28

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