Config file: To Be Generated
OpenVPN Client: https://openvpn.net/community-downloads/
 
Note: there’s an error with the Asus router, one must fix its OpenVPN DH Parameters with this
 
—–BEGIN DH PARAMETERS—–
MIIBCAKCAQEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb
IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft
awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT
mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh
fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq
5RXSJhiY+gUQFXKOWoqsqmj//////////wIBAg==
—–END DH PARAMETERS—–
 
Configure OpenVPN and Asterisk (http://www.pittnerovi.com/jiri/hobby/electronics/voip/)  to make VoIP calls by SIP/VPN protocol
 
Centos Install between 2 sites:
———– Site A ——————
yum install openvpn openssl -y
openvpn –keygen –secret /etc/openvpn/vpn.key
scp /etc/openvpn/vpn.key 192.168.16.150:/etc/openvpn/vpn.key
vi /etc/openvpn/server.conf
————- config file server in network A ————–
remote 192.168.16.150
float
port 8000
dev tun
ifconfig 10.0.0.1 10.0.0.2
persist-tun
persist-local-ip
comp-lzo
ping 15
secret /etc/openvpn/vpn.key
route 10.2.2.0 255.255.255.0
chroot /var/empty
user nobody
group nobody
log vpn.log
verb 1
————–
systemctl start [email protected]
ifconfig
  check for tunnel stats
ssh 192.168.16.150
hostname
vi /etc/openvpn/vpn.key
————— config file on client in network B —————–
remote 192.168.16.160
float
port 8000
dev tun
ifconfig 10.0.0.2 10.0.0.1
persist-tun
persist-local-ip
persist-remote-ip
comp-lzo
ping 15
secret /etc/openvpn/vpn.key
route 10.1.1.0 255.255.255.0
chroot /var/empty
user nobody
group nobody
log vpn.log
verb 1
—————–
systemctl start [email protected]
 
Now, edit the firewall
# iptables -A INPUT -i eth0(external interface) -p udp –dport 8000 -s 10.2.2.0/24(source network) -d 10.1.1.0/24(destination network) -j ACCEPT # iptables -P OUTPUT ACCEPT