DA-710 Series Linux
Managing Communications
3-26
Ethernet Bridging for Private Networks on Different Subnets
1.
Set up four machines, as shown in the following diagram.
Host A represents the machine that belongs to OpenVPN A, and Host B represents the machine that belongs
to OpenVPN B. The two remote subnets are configured for a different range of IP addresses. When this
configuration is moved to a public network, the external interfaces of the OpenVPN machines should be
configured for static IPs, or connected to another device (such as a firewall or DSL box) first.
2.
Generate a preset shared key by typing the command:
# openvpn --genkey --secret secrouter.key
3.
Copy the file that is generated to the OpenVPN machine:
# scp /etc/openvpn/secrouter.key 192.168.8.174:/etc/openvpn
ATTENTION
A preshared key is located at
/etc/openvpn/secrouter.key
. You can use it for testing purposes. We suggest
creating a new key for non-testing purpose.
4.
On machine OpenVPN A, modify the remote address in the configuration file
/etc/openvpn/tap0-br.conf
.
# point to the peer
remote 192.168.8.174
dev tap0
port 1194
secret /etc/openvpn/secrouter.key
cipher DES-EDE3-CBC
auth MD5
tun-mtu 1500
tun-mtu-extra 64
ping 40
up /etc/openvpn/tap0-br.sh
#comp-lzo
5.
Next, modify the routing table in the
/etc/openvpn/tap0-br.sh script
file.
#--------------------------Start---------------------------
#!/bin/sh
# value after “-net” is the subnet behind the remote peer
route add -net 192.168.4.0 netmask 255.255.255.0 dev br0
#----------------------------end---------------------------
