Configuring VPN-X server as NAT server on Mac OS X Tiger/Leopard

VPN-X provides a friendly GUI for Mac OS X and FreeBSD users to make a NAT server more easily. If you encounter any problem, please contact us.

VPN-X on Mac OS X Tiger screenshot

Open VPN-X "route configuration" panel and do the following configuration.

• Act as gateway: checked
• Act as NAT server: checked
• NAT interface: en0

Notes: Since VPN-X 2.4.1.35,VPN-X can help you get the default NAT interface automatically. You need not run the command to check.
The NAT interface should be your LAN interface name on your Mac OS X (Tiger/Leopard). You can use the command "ifconfig" to check.

ifconfig

For example: In our Test Mac OS X, we get the following information

apple-computer:~ root# ifconfig
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
inet 127.0.0.1 netmask 0xff000000
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
inet 192.168.1.28 netmask 0xffffff00 broadcast 192.168.1.255
ether 00:0c:29:18:9d:70
media: 10baseT/UTP <full-duplex> status: active
supported media: 10baseT/UTP <half-duplex> 10baseT/UTP <full-duplex>
tap0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1400
inet 192.168.240.1 netmask 0xffffff00 broadcast 192.168.240.255
ether d2:63:3a:d9:22:4f
open (pid 217)

NAT interface name is very important,or your VPN-X server will not work properly.


Add a route rule on “Client Route Table” for your VPN clients.

• network: 192.168.1.0
• netmask: 255.255.255.0
• gateway: 192.168.240.1
• metric: 5

if you want to access internet with server side IP, you should add route rule like this:

• network: 0.0.0.0
• netmask: 0.0.0.0
• gateway: 192.168.240.1
• metric: 1

Don't forget to click "Apply". After change route setting, you’d better tell your clients to restart VPN-X client to make sure the new route rule is working.