Openvpn installation

Server management - Vps and dedicated

Sunday, 01 March 2009 18:31 Last Updated on Sunday, 01 March 2009 18:52 Written by somer orbay

Before starting you have to add dag wieers repo from here

http://dag.wieers.com/rpm/FAQ.php#B 

If you are on a  vps then you`ll need your vps provider enable tun/tap devices for you.  If you are on a dedicated server you can issue following commands at ssh to create the device

mknod /dev/net/tun c 10 200

modprobe tun

Go to ssh

yum install openssl openssl-devel

2. Right, now you want to install OpenVPN, here are the commands,

yum install openvpn -y

#Now check that it works

service openvpn start
service openvpn stop

3. A few things to setup before you can make certificates, issue these commands,

find / -name "easy-rsa"

#you should get an output like this…

/usr/share/doc/openvpn-2.0.7/easy-rsa

#Now, make a copy of the easy-rsa directory, to /etc/openvpn/ ( make sure you #have put the right version number in i.e. mine was -2.0.7, change if needed)

cp -R /usr/share/doc/openvpn-2.0.7/easy-rsa /etc/openvpn/

cd /etc/openvpn/easy-rsa

chmod 777 *

mkdir /etc/openvpn/keys

4. You need to edit the vars file, located in /etc/openvpn/easy-rsa
You can use any editor you like, I used vi.

Change the line

export KEY_DIR=$D/keysto

export KEY_DIR=/etc/openvpn/keysAlso at the bottom of this file you will see something similar to this,

export KEY_COUNTRY=US
export KEY_PROVINCE=CA
export KEY_CITY=SOMEWHERE
export KEY_ORG="My Org"
export KEY_EMAIL=me@mydomain.comChange this to your own values.

5. Now its time to make the certificates, enter these commands

. ./vars
./clean-all
./build-ca  # just hit enter to the defaults apart from Common Name, this must be unique
# call it something like mydomain-ca

./build-key-server server
./build-key client1   # remember that common name must be unique e.g. use mydomain-client1
# and YES you want to sign the keys

./build-key client2  # do this step for as many clients as you need.

./build-dh

6. We are almost done now… right we need to create a few config files, you can download my template from here,

cd /etc/openvpnCode:
wget www.designpc.co.uk/downloads/server.conf   # make sure you change a few things in the server.conf file, like DNS
# servers

touch server-tcp.log~ this makes the log file..

touch ipp.txt this makes the IP reservation list.

7. You need to make a few changes to OpenVPN itself. Go to..

cd /etc/init.d/edit the openvpn file

#Uncomment this line (line 119)

echo 1 > /proc/sys/net/ipv4/ip_forward Add these lines below it, changing 123.123.123.123 to your public IP address,

 iptables -t nat -A POSTROUTING -s 192.168.2.3 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.4 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.5 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.6 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.7 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.8 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.9 -j SNAT --to 123.123.123.123
 iptables -t nat -A POSTROUTING -s 192.168.2.10 -j SNAT -to 123.123.123.123

Now install iptables if you don’t have it already,

yum install iptables

#test it

service iptables start
service iptables stop

8. Now for the client config files. If your client is a Windows machine, make sure you have installed OpenVPN, use the gui version, downloadable from here;

http://www.designpc.co.uk/downloads/openvpn-2.0.9-gui-1.0.3-install.exe

You need to copy a few files from the server to your client machine, here is the list, located in /etc/openvpn/keys/

## WARNING ## Use a secure way of transferring these files off the server, something like WinSCP.

ca.crt
client1.csr
client1.key
client1.crt

Put these files in this directory C:\Program Files\OpenVPN\config\

Now you need to make a client config, here is an example..

client
dev tun
proto tcp

#Change my.publicdomain.com to your public domain or IP address
remote my.publicdomain.com 1194

resolv-retry infinite
nobind
persist-key
persist-tun

ca ca.crt
cert client1.crt
key client1.key

ns-cert-type server

#DNS Options here, CHANGE THESE !!
push "dhcp-option DNS 123.123.123.123"
push "dhcp-option DNS 123.123.123.124"

comp-lzo

verb 3

Make sure you edit any of the lines with comments above them.

Call this file client1.opvn and put it in C:\Program Files\OpenVPN\config\

Make sure the file extension is .opvn not .txt

To connect right click on OpenVPN in the taskbar >> Connect

To test ping 192.168.2.1

If you get a response, you in business
...........................................................................................

Credits

Stanton Finley, for all the YUM configs
OpenVPN.net

Originally posted by stuartornum of webhostingtalk. http://www.webhostingtalk.com/member.php?u=58423