Cannot Connect to Local Network with 2 NIC's

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wipack
OpenVpn Newbie
Posts: 1
Joined: Wed Jul 25, 2012 2:10 am

Cannot Connect to Local Network with 2 NIC's

Post by wipack » Thu Jul 26, 2012 6:28 am

I have a Ubuntu Server with 2 NIC's running Access Server.

eth0 - Static Private ip 10.0.1.2
eth1 - Static Public ip (Primary Network Interface)

eth1 is configured to listen for VPN connections

eth0 is manually configured without a default gateway

When I VPN without the 1st NIC configured (eth0) I am able to connect to the vpn and surf the web using the VPN Public IP address ( This is the Default Method )

What I would like to do is be able to add eth0 and be able to also go to the local private network (eg: 10.0.1.5 )
This does not work. As soon as I configure eth0 I can VPN but I a not able to connect to anything.

I am trying to configure exactly what is stated in the OpenVPN Access Server System Administrator Guide : 2.2.2 Two Network Interfaces, One on Public and One on Private Network

Any help would be appreciated it.

yitzyn
OpenVpn Newbie
Posts: 2
Joined: Wed Mar 22, 2017 6:11 am

Re: Cannot Connect to Local Network with 2 NIC's

Post by yitzyn » Wed Mar 22, 2017 2:54 pm

Do you ever figure this out? Having similar issue

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novaflash
OpenVPN Inc.
Posts: 1073
Joined: Fri Apr 13, 2012 8:43 pm

Re: Cannot Connect to Local Network with 2 NIC's

Post by novaflash » Wed Mar 22, 2017 4:44 pm

I kind of hate to revive dead old threads, but alright then;

Most logical answer that I can think of: there is a default gateway configured on eth0 AND on eth1. When eth0 goes online, the default gateway route on eth1 is overruled and Internet access no longer functions. It's a fairly common newbie mistake to make; to configure default gateway on both interfaces. Don't. Configure it on only one network interface, the one with Internet access, and leave the other network interface without a default gateway. If you need to add specific routes for specific subnets, do this in /etc/network/interfaces with special parameters that run when the interface goes up or down, or implement the routes in the routing table in the OS on the command line and (if so desired) make them permanent across reboots.
I'm still alive, just posting under the openvpn_inc alias now as part of a larger group.

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