I have an old laptop that I decided to use as a server, with some samba shares and whatnot (making available some dvd rips and the like), and I'd like to be able to access the files in it from not only inside my home network, but also the outside network.
I read about port knocking, and that seemed like a decent idea — until I realized that because the server would be behind a router it might not be the best idea unless I get a new router that allows for it specifically. Then I read a bit more, and realized it might not be as safe as I'd originally gathered.
While investigating if my router allowed for port knocking, though, I came upon the notion of the DMZ — 'cause my router lets me configure that and all. My understanding of this, though, is that I'd need to make the whole server available to the world, and I'm not entirely sure how complicated it'd be to set up proper protection on a server in a router's DMZ, to later SSH into it from the outside.
Finally, while trying to get some answers out there, I also crossed paths with the idea of maybe getting a RaspberryPi and making it a VPN server so I can VPN into my home network. However, once again, not sure how vulnerable to exploitation that'd be.
I have a limited knowledge of security principles, not being a pro or anything, hence the doubt on this. My knowledge of iptables, for instance, is very limited, so I wouldn't know how to properly protect the router if I put it in the DMZ.
Is one of the three methods mentioned above generally preferred, in terms of safety? And what methods of securing it are generally recommended too? Bonus points: is one of them easier to set up too?