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| Subject: | Re: PPTP |
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| Date: | Sun, 25 Sep 2005 09:27:21 +0200 |
Matt Mckinley wrote:
I have a linux IPtables firewall (latest version) that is in bridging mode. There is another firewalling device behind it that is performing NAT. When a host behind that firewall connects to a PPTP server on a routable IP address, it appears that the IPTables linux box is breaking the connection. When we remove that device, the connection works fine. Does anyone have any thoughts on what might cause this behavior? Thanks!! -Matt
as far as i remember PPTP protocol use a second GRE connections that is started from the REMOTE PPTP Concentrator to the client requesting the pptp connection. in fact on a PIX you have to add the "fixup command" to deal with this issue. check here http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_configuration_example09186a0080094a5a.shtml i don't know if iptables has a conntrack module designed to deal with this problem, if not you should need a 1-1 NAT for each client needing the pptp connection. bye
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