MikroTik

Hi there,

I have a Routerboard with v5.24 installed that I wish to connect to a remote PPTP server and route all traffic through it. So far I have successfully set this up using online guides and when connected to a commercial VPN service like hidemyass.com, it stays connected and routes all traffic correctly. However, when I try to route traffic through my own PPTP servers, the connection always drops after around 1m20s of connection, then reconnects and does the same over for ever. When using torch to view the connection, I see all outbound traffic being routed to the PPTP server but absolutely nothing comes back.

With any other system, the PPTP server works fine. I can use my Windows PCs, Linux PCs, iPhone and Android tablet with the PPTP server fine - the connection never drops out and the tunnel works fine. The PPTP server is a Ubuntu 12.04 VPS in a datacentre that I have set up myself. I have 5 geographically isolated servers all with PPTP running and I have the same problem with each.

I have tried two different commercial PPTP servers to test my set up and these work perfectly, but I naturally want to use my own servers. I am aware of the security risks of PPTP and this is not a big issue for my application.

Would be very grateful to hear from anyone who can shed some light on this. I cannot detect whether this is a router problem or a server problem.

Mark.

I have the same problem! PPTP clients on Windows and OSX will connect to PoPToP on my servers but my RB750G won't stay connected. It authenticates properly but then no data comes back. I went over all of the authentication and encryption settings and everything checks out.

I've also used it with HideMyAss without any problems other than their servers being oversold.

Ah, I just came on to update that I have managed to resolve this.

In my /etc/pptpd.conf I had:

localip = [server's external IP]
remoteip = 10.1.0.1-100

I changed this to:

localip = 10.1.0.1
remoteip = 10.1.0.2-100

and everything works fine now. Check your configuration and see if you have the same problem.

Mark.

@cblonde - if you're setting up a Debian-based system, I have written a script that sets up PPTP on a system that works with my RouterBoard: www.markmearns.com/sandbox/pptp.sh - still in testing but sets up a working PPTP server on a Ubuntu VPS with PPP enabled in under a minute.

Mark.

Thanks Mark! I have the same settings in pptpd.conf. I'm not in a position to test it right now but what you're proposing makes sense. I'll try it and report back.

I changed the local IP per your suggestion and the connection works as expected now. Thanks.

I have one other problem that you may have had to deal with. If I set the MTU of my PPTP connection to 1500 the actual MTU of the established connection is 1496. This means I have to change the MTU setting of everything on my network to 1496 to get them working properly. I see in your script you're setting the server interface MTU to 1400. Did you find a way to work around setting the MTU on all your devices?