Thats the network: http://imgur.com/Xh5tHEm
Network 192.168.58.X is behind a squid proxy which blocks different websites for the users in the network and it works without any problems. there are special servers in this network which are monitored via VPN from an external network using the PPTP VPN client. Now the Problem is, that the pptp connection cannot pass the Proxy. Even if i ping the 192.168.58.x network from the 192.168.20.x network, it does not work. I already configured a port forwarding on the router for port 1723 to the proxy device, but how do i configure the proxy to forward the traffic to the vpn client?
thanks!
Squid is an HTTP proxy. It can only proxy HTTP and straight TCP connections (with CONNECT). PPTP relies on GRE, and squid cannot proxy that.
What you want is impossible, sorry.
so there is no way to bypass the proxy to the vpn server?
You have to go around the proxy software. How you do that depends on what your network looks like and you haven’t told us that.
That is totally possible if you have control of the egress traffic policy for the network behind the proxy. This is something that needs to be done on the firewalls.
Bypassing the proxy is not the same thing as tunneling through it.
the vpn server is directly behind the squid proxy. can i do it with the help of iptables?
yeah i want to tunnel through it. the network behind is a domain with around 40 computers and a DC as well as a mesos cluster which should be monitored with help of the vpn server
You wouldn’t tunnel through the proxy as such, you’d usually bypass it for non HTTP/HTTPS traffic.
Is it an explicit or transparent proxy?
Then the VPN traffic shouldn’t need to go through it depending on the network topology. A diagram would help us understand the setup.