Topology:

host 1

vpn-gw 1 <

> vpn-gw 2

host 2

<--192.168.50.0/24--> 10.15.109.36 10.15.109.5 <--192.168.1.0/24-->

Setup:

  1. Install the openswan package. Now we got 2 main files: /etc/ipsec.secrets and /etc/ipsec.conf
  2. Edit ipsec.secrets for vpn-gw 1:
    • 10.15.109.36 10.15.109.5 : PSK "password
  3. Edit ipsec.secrets for vpn-gw 1:
    • 10.15.109.5 10.15.109.36 : PSK "password"

  4. Edit ipsec.conf for vpn-gw 1 & vpn-gw 2 (same exact stuff):

    • conn vpn authby=secret left=10.15.109.36 leftsubnet=192.168.50.0/24 leftnexthop=10.15.109.5 right=10.15.109.5 rightsubnet=192.168.1.0/24 rightnexthop=10.15.109.36
  5. Restart ipsec:
    • /etc/init.d/ipsec restart
  6. Now you can ping from host 1 to host 2!