[Openswan Users] Windows XP L2tpipsec client connecting to Ubuntu server

[Mike Giles]

Hi,
I have a Ubuntu server which I'm trying to connect to with a Windows XP
client (L2tpipsec) I'm using PSK at the  moment.
Ubuntu 2.6.32.9
Openswan IPSEc 2.6.25
Xl2tpd 1.2.0

I have followed:
http://rootmanager.com/ubuntu-ipsec-l2tp-windows-domain-auth/setting-up-
openswan-xl2tpd-with-native-windows-clients.html

I can sometimes connect ok.

However the server often generates ICMP destination port unreachable
(1701) in reply to ESP packets (Destination port 4500).

I have attached a failed connect and a successful connect. (tcpdump on
server side)
The server is connected via a usb mobile broadband modem (using a static
public IP address NATed to 10.8.11.254).

I have tried connecting with no rules setup in iptables and with rules
accepting the specific ports (500,4500 and 1701).

Any suggestions would be very helpful.

Thanks & Regards,
Mike

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