VPN
From dghartung.com/docs
Strongswan host-host and host-roadwarrior setup
Credits and Links
Jacco de Leeuw's useful VPN page This howto is heavily based on this page!
Install gmp and gmp-devel
yum install gmp gmp-devel
Download Strongswan
cd /usr/local/src wget http://download.strongswan.org/strongswan-2.8.6.tar.bz2
Unpack it, make it, install it
tar -jxvf strongswan-2.8.0.tar.bz2 cd strongswan-2.8.0
If your clients are behind an NAT Device you may need to enable transport mode as shown here NAT-T
make programs make install
View this page to generate certificates: CA
Configure your /etc/ipsec.secrets
# /etc/ipsec.secrets - strongSwan IPsec secrets file : RSA name-this-key.pem "your-password-silly"
Edit your /etc/ipsec.conf file to look like these based on what you need
host-to-host or net-to-net roadwarrior-to-net-win-xp roadwarrior-behind-nat-linux real-ipsec.conf Here is my "real-world" working example with some of the particulars changed.
Configure l2tpd
If you use Shorewall Firewall look at this page: Shorewall Config for VPN
