Part 2 - Making OpenVPN work as a Client
When we want to connect to Office network from an external location or from home, then we need to setup our Linux box to establish communication with the server at the office via a secured link over the internet. In this part, I will list down the steps needed to establish a client communication.
For you to connect to your Office network where VPN is installed, your server administrator would have given you the following files:
- a .csr file (like for e.g. yourname.csr) - a .crt file (like for e.g. yourname.crt) - a .key file (like for e.g. yourname.key) - a .conf file (like for e.g. yourname.conf)
A sample <<yourname.conf>> file:
[root@computer /]# vi yourname.conf
#yourname.conf tls-client client dev tun proto udp tun-mtu 1400 remote vpn_server_ip_address 1194 resolv-retry infinite nobind persist-key persist-tun ca /etc/openvpn/ca.crt cert /etc/openvpn/yourname.crt key /etc/openvpn/yourname.key cipher BF-CBC comp-lzo verb 3
As you can see from the above file, you need to COPY the file <<yourname.csr>>, <<yourname.crt>>, <<yourname.key>>, <<yourname.conf>> to the location /etc/openvpn/. If you want to setup a different folder for having these files separately, then give the appropriate path inside <<yourname.conf>> file.
Inside <<yourname.conf>> file, replace vpn_server_ip_address with the IP address given by your server administrator.
Now you are good to go. Issue the command
[root@computer /]# openvpn --config yourname.conf
Once the connection is established you will get a line stating that "Initialization sequence completed" which signals that client communication with the remote location is instantiated. Now you can browse through the files in the remote server wherever you are.
Notes: - Inside <<yourname.conf>> file, DO NOT have ~ (tilde) mark to signify the root. This is not recognized from within the .conf file and it will return an error. - Check the line that states 'cipher' in <<yourname.conf>>. Here I have stated that BF-CBC as my 128 bit cypher encryption algorithm for establishing my connection. Depending on the information given by your server admin, you may need to change this part.
