I have activated the VPN via network settings. What is the purpose of it? Does this mean that my NAS and my files are more secure now from attacks?
Might want to read this post…
Short answer: No
And if you believe it is, you should stop to have your DS exposed to the open Internet. Learn the basics before you think about connecting again.
It is not the VPN that would be insecure. But your obvious lack of knowledge is the problem. One that you can fix yourself, by learning.
If you don’t know what the purpose of a VPN is, you should probably start by going to r/VPN and reading the faq in the sidebar, and seeing what kinds of questions and answers appear in that forum.
The real questions about VPNs to ask are: what does a VPN hide and who is it hidden from?
If you really want to protect your NAS from attacks from the outside, first don’t expose the ports outside your network, just accept local network access.
Then install Tailscale on your NAS (create a free account) install it also on devices that you probably going to pick other than your local network, phone, laptop, etc…
What tailscale does is to securely merge your devices in the same network, even you are in other country.
For your Tailscale devices it’s the same lan, like you were connected to your router.
This is more secure because you not exposing your router services to the world.
so in this context express vpn is a vpn provider that just encrypts the traffic leaving your device toward the internet.
this doesn’t secure your network it just encrypts the traffic leaving your device so your isp can’t see what you’re doing.
express vpn however now is the entity with that data.
i’d remove express vpn from the NAS. it makes no sense unless you’re torrenting and want to hide your traffic from your isp
Now, if you wanted a vpn to secure your traffic between your devices when you’re outside your network then that makes sense. most popular and easy to setup around here is tail scale. this also has the function of letting you access your internal services when you’re outside your home.
OP, you clearly need to increase your knowledge here but one thing I will say is please don’t fall for the fear mongering about exposing your NAS to the internet.
Synology devices in general are designed to be quite robust and accessible from outside your local network and all you really need are some basic common sense security precautions and regular backups.
You’ve arguably made your NAS less secure by connecting to someone else’s network. Why would you do this when you don’t know the purpose of it?