I've setup a VPN server using Debians pptpd. This all works, but I want to restrict incoming connections so they can only access ports on the VPN server and not get access to other machines on the VPN servers local network.
I'm guessing this is a firewall rule? but i'm new to linux so am struggling a bit...
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The VPN Server is also hosting an SVN server, which is its real purpose, and the only service I want it to expose to incoming connections. I guess I could expose the SVN server directly, but I'm not confident that I could secure this correctly, so a VPN seemed to give an additional layer of security.