Step 1. Install PPTPD
If your OS is CentOS/RedHat 5:
yum install ppp
cd /usr/local/src
wget http://poptop.sourceforge.net/yum/stable/packages/pptpd-1.3.4-2.rhel5.x86_64.rpm
rpm -Uhv pptpd-1.3.4-2.rhel5.x86_64.rpm
If your OS is CentOS/RedHat 6:
yum install ppp
cd /usr/local/src
wget http://poptop.sourceforge.net/yum/stable/packages/pptpd-1.3.4-2.el6.x86_64.rpm
rpm -Uhv pptpd-1.3.4-2.el6.x86_64.rpm
If you are using Ubuntu:
apt-get install pptpd
Step 2. Edit IP setttings in /etc/pptpd.conf
vi /etc/pptpd.conf
localip 192.168.0.1
remoteip 192.168.0.101-200
Step 3. Add user account in/etc/ppp/chap-secrets (assign username and password)
vi /etc/ppp/chap-secrets
usernameForuser1 * setpassword1here *
usernameForuser2 * setpassword2here *
Step 4. Optional settings in /etc/ppp/options.pptpd
vi /etc/ppp/options.pptpd
ms-dns 8.8.8.8
ms-dns 4.4.4.4
Step 5. Enable network forwarding in /etc/sysctl.conf
vi /etc/sysctl.conf
net.ipv4.ip_forward = 1
use the following command to apply the change:
sysctl -p
Step 6. Configure firewall
iptables -A INPUT -i eth0 -p tcp --dport 1723 -j ACCEPT
iptables -A INPUT -i eth0 -p gre -j ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
iptables -A FORWARD -i ppp+ -o eth0 -j ACCEPT
iptables -A FORWARD -i eth0 -o ppp+ -j ACCEPT
service iptables save
service iptables restart
If you are using CSF firewall, you may refer to this post on firewall settings.
Step 7. Start PPTP VPN server
If your OS is CentOS or Redhat, using the following command:
service pptpd restart
To start PPTP Daemon automatically when rebooting next time, use command:
chkconfig pptpd on
Credit http://www.photonvps.com/billing/knowledgebase.php?action=displayarticle&id=58
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