[Openswan Users] UDP: Bad checksum

[Jacco de Leeuw]

Lars Bakker wrote:

> I'm having serious trouble setting up openswan (l2tp/ipsec) behind a NAT 
> device. There is no problem with the ipsec SA negotiation, but as soon 
> as the SA is established and the l2tp-packages get decrypted the kernel 
> reports: "UDP: Bad checksum". 

Could be an MTU problem or a NAT router trying to be 'helpful' by
doing IPsec passthrough.

Can you confirm that the problem does not occur when there is no NAT?
Or just single NAT?

Jacco
-- 
Jacco de Leeuw                         mailto:jacco2 at dds.nl
Zaandam, The Netherlands           http://www.jacco2.dds.nl
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