Setup PPTP VPN Server on CentOS 6

Setup VPN server
Install the required packages.

yum install -y pptpd

Configure the PPTP settings. The "ppp" configuration files are important for pptpd. First, configure /etc/ppp/options.pptpd, as follows. If desired, you may change the DNS servers.

name pptpd
refuse-pap
refuse-chap
refuse-mschap
require-mschap-v2
require-mppe-128
proxyarp
lock
nobsdcomp 
novj
novjccomp
nologfd
ms-dns 8.8.8.8
ms-dns 8.8.4.4

Next, add users to the PPTP VPN service by editing /etc/ppp/chap-secrets. Change the username and passwords accordingly.

vultr1  pptpd   P@$$w0rd  *
vultr2  pptpd   P@$$w0rd2  *

Configure the pptpd daemon settings by editing /etc/pptpd.conf. Use the following example configuration. You can change the IP address ranges if needed.

option /etc/ppp/options.pptpd
logwtmp
localip 192.168.80.1
remoteip 192.168.80.101-200

Next, edit /etc/sysctl.conf to enable IP forwarding.

sed -i 's/^net.ipv4.ip_forward.*/net.ipv4.ip_forward = 1/g' /etc/sysctl.conf
sysctl -p

Configure routing with iptables.

iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 1723 -j ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -s 192.168.80.0/24 -j MASQUERADE
service iptables save
service iptables start
Start the service.
service pptpd start

Your PPTP server setup is complete. Now you can connect to your own PPTP VPN server from your PC or mobile device.