sudo apt-get install pptpd
If the prompt cannot be found, then update apt
sudo apt-get update
Modify three files:
/etc/pptpd.conf
localip 192.168.0.1 The ip of the VPN server (not the real ip, but an ip of the pptp subnet)
remoteip 192.168.0.100-192.168.0.200
/etc/ppp/pptpd-options Set DNS
ms-dns 8.8.8.8
ms-dns 8.8.4.4
/etc/ppp/chap-secrets set username and password
# client server secret IP addresses
username * password *
Restart the pptp service:
sudo /etc/init.d/pptpd restart
Enable IP forwarding
# sudo nano /etc/sysctl.conf
Uncomment: net.ipv4.ip_forward=1
Reload configuration: sudo sysctl -p
Add forwarding rules: # sudo nano /etc/rc.local
Add two lines before exit 0 :
iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -o eth0 -j MASQUERADE
iptables -A FORWARD -p tcp --syn -s 192.168.0.0/24 -j TCPMSS --set-mss 1356
This chestnut uses 192.168.0 as the PPTP subnet
Restart server reboot
https://help.ubuntu.com/community/PPTPServer
The above method may not work for VPS (VPS does not have eth0 -j MASQUERADE )