An external DHCP server

In this recipe, we will configure a bridged OpenVPN server so that it uses an external DHCP server to assign addresses to the OpenVPN clients to further increase the integration of remote clients with the clients already present on the server-side LAN.

Getting ready

We use the following network layout:

Set up the client and server certificates using the first recipe from Chapter 2, Client-server IP-only Networks. For this recipe, the server computer was running CentOS 6 Linux and OpenVPN 2.3.10. The client was running Windows 7 64 bit and OpenVPN 2.3.10. For this client, keep the client configuration file example3-2-client2.ovpn from the Enabling client-to-client traffic recipe at hand.

How to do it...

1. Create the server configuration file:

           proto udp 
           port 1194 
           dev tap0 
    
           server-bridge 
           push "route 0.0.0.0 255.255.255.255 net_gateway" 
    
           tls-auth /etc/openvpn/cookbook/ta.key 0 
      ...