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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Just as a follow up to this:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>With Paul’s help we tracked down the likely culprit. It seems that xl2tpd is trying to send communicate across the IPSec tunnel before the SA is established in both directions. As such the first packet (s) do not get through and xl2tpd stalls. Unfortunately it blocks while it’s waiting leading to the problem I noticed.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Paul did suggest I could add KLIPS support to my Debian kernel (KLIPS will cache packets sent before the SA is fully established) but that is deviating a bit too far off the mainstream for my application. My knowledge of Linux doesn’t extend quite that far and I don’t have time right now to learn.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I’ve worked around it by ditching the L2TP part of my VPN set up. IPSec is quite capable, I now realise, of establishing routes between subnets so a “pure IPSec” VPN seems to work very well for me. It’s faster (1.5ms ping round-trip across my LAN compared to 6 to 10ms with the L2TP tunnel). I started out down the L2TP route more by accident, probably because that’s generally what Windows clients use and so there’s a lot of talk about it online. People doing IPSec VPNs seem to use Cisco a lot of the time so I had foolishly disregarded this.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>So, thanks to the mailing list for your help!<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Giles.<o:p></o:p></span></p></div></body></html>