root@t-Aspire-5742:/# sudo ipsec verify
Checking your system to see if IPsec got installed and started correctly:
Version check and ipsec on-path                                 [OK]
Linux Openswan U2.6.37/K3.5.0-42-generic (netkey)
Checking for IPsec support in kernel                            [OK]
 SAref kernel support                                           [N/A]
 NETKEY:  Testing XFRM related proc values                      [FAILED]
  Please disable /proc/sys/net/ipv4/conf/*/send_redirects
  or NETKEY will cause the sending of bogus ICMP redirects! [FAILED]
  Please disable /proc/sys/net/ipv4/conf/*/accept_redirects
  or NETKEY will accept bogus ICMP redirects                    [OK]
Checking that pluto is running                                  [OK]
 Pluto listening for IKE on udp 500                             [OK]
 Pluto listening for NAT-T on udp 4500                          [OK]
Two or more interfaces found, checking IP forwarding            [FAILED]
Checking for 'ip' command                                       [OK]
Checking /bin/sh is not /bin/dash                               [WARNING]
Checking for 'iptables' command                                 [OK]
Opportunistic Encryption Support                                [DISABLED]
sudo sysctl stuff.you.want.to.change=newValue. Pour rendre vos modifications persistantes, vous devez modifier le/etc/sysctl.conf.