Synology DS Setup:
Log in to your Synology DS using the admin account and install the OpenVPN server from within Package Center.
Once installed, start VPN Server and enable OpenVPN under OpenVPN Server > Settings > OpenVPN.
A pop-up message will appear instructing you to make sure UDP port 1194 is open.
Select a dynamic IP address for the IPs that will be assigned for the OpenVPN clients and the maximum number of connections possible.
Also make sure that if you are behind a router or other NAT that the port is forwarded to the Synology DS OpenVPN Server.
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Install OpenVPN
Download and install the OpenVPN application for your OS from OpenVPN community downloads (http://openvpn.net/index.php/open-source/downloads.html) . Install using the defaults.
Getting the configuration from the Synology OpenVPN server
Before the client software can be configured, a few files (specifically the OpenVPN configuration files and the certificate) need to be downloaded from the Synology DS. From the DS, go to OpenVPN Server > OpenVPN and click on Export Configuration. This will download a zip file containing the two needed files plus a third README file. You can either refer to the README for instructions or simply continue reading.
Configure the OpenVPN client software
Open windows explorer and navigate to “C:\Program Files (x86)\OpenVPN\config”. Copy the openvpn.opvn and ca.crt files from the openvpn.zip file you downloaded earlier to this directory.
Right-click on openvpn.ovpn and open it with notepad and make the edits shown below:
>>> Change the line starting with remote to specify your server’s IP address or hostname. For example, if your OpenVPN server was at server1.domain.com, change it as follows:
remote server1.domain.com 1194
If your host’s IP address frequently changes, uncomment the float option.
Also, if you want to redirect ALL traffic across the OpenVPN connection (preferred), uncomment the redirect-gateway option.
Connecting to the OpenVPN Server
Right-click the OpenVPN GUI desktop icon and select “Run as administrator”.
The OpenVPN GUI icon will appear in your taskbar, and it will appear red. Right-click on it and select Connect. You will be prompted for your username and password (as used on your Synology DS) to connect.