[Durham] connecting to L2TP IPSec vpn

[Peter Grandi]

> [ ... ] It appears those how to's are purely to set up a
> strongswan server then connect a mac or iphone client to it?

IPSEC is just a way to encrypt packets, so it is symmetric.

L2TP is the real "VPN" in your setup, and it is needed on both
sides.

The 'xl2tpd' daemon does the client side as well as the server
side of L2TP; the server side is configured in the 'lns' section
and the client side in the 'lac' section, and the configuration
is fairly similar.

I have done some more web searching and these links seem
apposite:

  http://strongvpn.com/forum/viewtopic.php?id=788
  http://www.jacco2.dds.nl/networking/linux-l2tp.html
  http://trinityhome.org/Home/index.php?wpid=167&front_id=18
  http://www.natecarlson.com/2006/07/10/configuring-an-ipsec-tunnel-with-openswan-and-l2tpd/

Note that depending on what you want to achieve, you may not
want the PPP client to set or replace the default route, or the
peer DNS.