PPTP Setup: How to put remote clients into a "virtual" local network?

BigglesZX · 02-07-2009, 05:55 AM

Hi all,

Apologies for the possibly slightly confusing title - let me elaborate.

I have a Slicehost VPS and I'm trying to set up PPTPD on it. I only have one IP address (the public IP of the box). All the PPTPD howto's I've seen rely on assigning remote clients IPs from the local subnet (e.g. the PPTD server's local IP is 192.168.0.20, and remote IPs are taken from a pool of 192.168.0.30-40).

However I don't think I can do that as I only have the one IP address on Slicehost's network - that public IP (and all other IPs in the segment are public).

So what I really want to do is to be able to create a private LAN segment or virtual network adapter and have VPN clients assigned addresses in that segment, then routed out onto the Internet effectively using the PPTPD box as a router.

Does this sound insane? Am I missing something obvious? If not, any tips on the configuration I would need to achieve this?

I am using Ubuntu Hardy (LTS).

Any help would be massively appreciated. Many thanks in advance!

Biggs

jimjones · 02-08-2009, 12:05 AM

my knowledge of vpn's is pretty sketchy but here's a few answers:

as for you just having one ip - correct but you will set up a 'dial up' service there which will connect and then assign the client a private ip adress i.e. 192.168.x.x
this virtal network you can connect to your home network

oh and dont worry -the software will do most of the work

i dont know if debian has a vpn software but i think this one will work on most distros: http://en.wikipedia.org/wiki/OpenVPN

BigglesZX · 02-09-2009, 08:15 AM

Thanks for your reply.

Having read around the subject a bit more, I am now more sure of what it is I need to do.

I need to know how to configure a virtual local network adapter and route packets from that network to the real network/Internet.

If what I'm thinking is right, I should then be able to assign addresses from that private network to incoming PPTP clients and have their traffic routed onto the Internet.

So it's less of a PPTP-specific issue and more of a general networking issue.

Any pointers to achieve this end would be hugely appreciated! I have tried a lot of Googling but my terminology must be a bit off, as I haven't turned up much.

Thanks again,

Biggs