Using an external DHCP server

In a bridged setup, it is possible to integrate the clients into the server-side network even further. In most networks, a DHCP server is used to assign IP addresses. Normally, OpenVPN assigns IP addresses to its clients using either the following command:

server 10.200.0.0 255.255.255.0

Or, using the following command:

server-bridge 192.168.3.15 255.255.255.0 192.168.3.128 192.168.3.250

It is also possible to use an external DHCP server to assign addresses to the OpenVPN clients. To achieve this, simply remove the specification of any IP address ranges after the server-bridge option, as shown in the following (Linux-oriented) configuration file:

tls-server
proto udp
port 1194

dev tap0 ## the '0' is extremely important

server-bridge

remote-cert-tls client
tls-auth /etc/openvpn/movpn/ta.key 0
dh       /etc/openvpn/movpn/dh2048.pem
ca       /etc/openvpn/movpn/movpn-ca.crt
cert     /etc/openvpn/movpn/server.crt
key      /etc/openvpn/movpn/server.key

persist...