VPN

VPNs can provide some additional security benefits, such as masking the user's IP address and encrypting traffic,
they do not necessarily provide an extra layer of security for OpenSSH connections.
In fact, using OpenSSH over a VPN can add complexity and increase the attack surface, as it requires additional software to be installed and configured on both the client and server sides.

It's worth noting that OpenSSH traffic is already encrypted, and double encryption of traffic provides no benefit.
Additionally, any firewall tool such as iptables is better used in combination with OpenSSH rather than VPN,
as it allows for more fine-grained control over network traffic and can better protect against certain types of attacks.

Using a VPN with OpenSSH can add an extra link to the chain, and if the VPN server experiences errors, it can cause problems accessing the OpenSSH server.
Therefore, it may not be a suitable solution in places where 100% uptime is required.
The security of each approach ultimately depends on the specific use case and requirements of the user.
It's important to thoroughly assess the benefits and risks before implementing any security solution,
and to ensure that all software is properly configured and maintained to mitigate any potential vulnerabilities.