linux firewall configuration to support Nortel Contivity client

Grant Taylor gtaylor at
Mon Aug 15 07:36:05 CEST 2005

Michael you may want to try sniffing the traffic that your notebook gives off when it has it's ""VPN up and running.  If the traffic is IP/ESP (IP protocol 50) then the traffic is an IPSec tunnel.  If the traffic is IP/GRE (IP protocol 47) then the tunnel is a GRE tunnel.

Grant. . . 

Michael wrote:
> Hi,
> At home I have a linux box ( kernel) acting as my gateway. It
> is running nat, upnpd & iproute2 all quite happily.
> What I want to do next is make the vpn client (Nortel Contivity) on my
> work laptop play nicely. I've been looking at the ip_nat_pptp &
> ip_nat_proto_gre patches from patch-o-matic.
> I'm not sure what kind of tunel Contivity tries to establish (or much
> else about it works) Has anybody out there setup something similiar to
> this? Or know much about Contivity sets up a vpn?
> --
> Michael
> oni at

More information about the netfilter mailing list