[Openswan Users] PPP issues (was Re: openswan + l2tpd + iptables problem)

[Paul Wouters]

On Thu, 19 Oct 2006, mechanix at debian.org wrote:

> I discovered something else: when I run tcpdump on the gateway, it seems
> to `forget' how to reach the client - which seems to coincide with the
> moment packets stop getting sent to the client - seeing that it performs
> arp requests, which are never answered.
>
> Does anyone know what could be up with that?

Michael suggests this could be because you are losing arp packets.
(then i looked at the log below, and indeed, it looks like that is the case)

> 22:57:44.146242 IP GW.IP.ADDR.ESS.4500 > REM.OTE.ADDR.ESS.4500: UDP-encap: ESP(spi=0xb1f325b8,seq=0x10), length 52
> 22:57:46.267167 arp who-has REM.OTE.ADDR.ESS tell GW.IP.ADDR.ESS
> 22:57:48.969962 IP REM.OTE.ADDR.ESS.4500 > GW.IP.ADDR.ESS.4500: UDP-encap: ESP(spi=0x537cb518,seq=0x17), length 76
> 22:57:48.975399 arp who-has REM.OTE.ADDR.ESS tell GW.IP.ADDR.ESS
> 22:57:49.975476 arp who-has REM.OTE.ADDR.ESS tell GW.IP.ADDR.ESS
> 22:57:50.975562 arp who-has REM.OTE.ADDR.ESS tell GW.IP.ADDR.ESS

> Oct 19 22:57:42 scotos l2tpd[20820]: ourtid = 12824, entropy_buf = 3218

Does the problem go away with xl2tpd ? We did quite some fixing of the l2tpd code.

Paul
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