User`s manual
IA260-261-262 EM-2260 LX User’s Manual  Managing Communications 
3.  Create a configuration file named A-tap0-br.conf and an executable script file named 
A-tap0-br.sh on OpenVPN A. 
# point to the peer 
remote 192.168.8.174 
dev tap0 
secret /etc/openvpn/secrouter.key 
cipher DES-EDE3-CBC 
auth MD5 
tun-mtu 1500 
tun-mtu-extra 64 
ping 40 
up /etc/openvpn/A-tap0-br.sh 
#----------------------------------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 ------------------------------ 
Create a configuration file named B-tap0-br.conf and an executable script file named 
B-tap0-br.sh on OpenVPN B. 
# point to the peer 
remote 192.168.8.173 
dev tap0 
secret /etc/openvpn/secrouter.key 
cipher DES-EDE3-CBC 
auth MD5 
tun-mtu 1500 
tun-mtu-extra 64 
ping 40 
up /etc/openvpn/B-tap0-br.sh 
#---------------------------------- Start---------------------------- 
#!/bin/sh 
# value after “-net” is the subnet behind the remote peer 
route add -net 192.168.2.0 netmask 255.255.255.0 dev br0 
#---------------------------------- end ----------------------------- 
Note: Select cipher and authentication algorithms by specifying “cipher” and “auth”. To see 
which algorithms are available, type: 
# openvpn --show-ciphers 
4.  Start both of OpenVPN peers, 
# openvpn --config A-tap0-br.conf& 
# openvpn --config B-tap0-br.conf& 
If you see the line “Peer Connection Initiated with 192.168.8.173:5000” on each machine, the 
connection between OpenVPN machines has been established successfully on UDP port 5000. 
5.  On each OpenVPN machine, check the routing table by typing the command: 
# route 
Destination Gateway Genmsk  Flags  Metric Ref  Use  Iface 
192.168.4.0 * 255.255.255.0 U  0  0  0 br0 
192.168.2.0 * 255.255.255.0 U  0  0  0 br0 
192.168.8.0 * 255.255.255.0 U  0  0  0 eth0 
Interface eth1 is connected to the bridging interface br0, to which device tap0 also connects, 
whereas the virtual device tun sits on top of tap0. This ensures that all traffic from internal 
networks connected to interface eth1 that come to this bridge write to the TAP/TUN device 
that the OpenVPN program monitors. Once the OpenVPN program detects traffic on the 
virtual device, it sends the traffic to its peer. 
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