When successfully making a PPTP connection to a remote VPN server with the built-in Mac OS X client, you find that you can’t connect to hosts on the other side of the VPN tunnel. You can still connect to the Internet and LAN hosts. The root issue is that, by default, OS X has no reason to send traffic across the VPN tunnel. A reason must be provided. I discuss 3 ways to handle this issue, including /etc/ppp/ip-up.