I'm trying to set up a pptp-server on my vps, but I'm lost as to what the "localip" and "remoteip" settings have to be.
My VPS has only 1 IP address, so I don't really know what to put as a remoteip.
The localip addresses are the ones who are given to the clients on the server itself, the remoteip go to the client. For example, your local localip is 10.0.0.10-14 (that's 5 connections) and remoteip is 10.0.0.15-19. After the client connects he has got 10.0.0.15 on his side (the P-t-P connection) and on your system the ppp connection will have ip 10.0.0.10.
For more detailed explanation of pptpd.conf see: http://www.linux.org.au/~quozl/pptp/pptpd.conf.5.html