Before you begin, choose a UDP port (or ports) that you want to use for
your OpenVPN connection. You might ask, why does a port matter?
Outgoing port restrictions
Some networks restrict ports to control outgoing traffic. For example, a
network wants to prevent torrents (port ranges 6700-6999) or defend again
viruses that use Window’s file sharing (135-139). A network might block
the VPN port 1194 intentionally.
Using a common port can by-pass that restriction.
Seeking to be anonymous
Using port 1194 announces to your ISP or network admin that you are using
a VPN. You might want to hide that you are using a VPN.
Using another port can help mask a VPN tunnel.
It takes a sophisticated operation to detect a VPN.
Select a well-known UDP port that is likely to be open (DNS, NTP),
that masks your usage (masquerade your data as a streaming video or game),
or pick a port at random.
you have a file with an extension .ovpn in the root (~)
directory.
Edit the .ovpn file using nano or another editor and verify that
the IP address, port and protocol are correct.
The configuration might work on some systems, but there is a
configuration error that prevents the client from communicating with the
VPN server. Please continue to the next step to correct the invalid
configuration.