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Old 10-16-2001, 09:50 AM   #1
LQ Newbie
Registered: Jun 2001
Location: Frankfort, IL
Distribution: Suse 7.1
Posts: 9

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Question ipchains & VPN connection

I have a linux box set up to masq several internal windows machines on my network. All is working well. I also have a laptop from work that I want to use to connect to my office network via a company vpn setup. Before adding the linux box as the router/gateway, I was doing this via ICS on windows.

At the moment, my vpn connection won't work. The way I think it's "supposed" to work is that I issue a ping command to the office server which then responds with a dialog box requesting user id & password. It then establishes a secure connection and I'm off to the races.

When I connect the laptop to my hub, I can access the internet just fine. I can successfully ping the office server, get the login dialog box, and enter my userid and password. However, I get an error message that the office server can't communicate with my machine.

I am assuming this is due to an ipchain rule that's keeping this type of communication out. The reason I say this is because I had a similar problem with my windows firewall until I set up the office server's IP address as a trusted address. Being really new to the ipchains stuff, how can I set up a specific IP address in the same manner (i.e. trusted)?

I don't know what port the vpn connection is communicating via or any other details beyond the office server's ip address. FYI, eth0 is connected to my cable modem with a static IP and eth1 is connected to my LAN with an IP of

Any help y'all can offer would be great!!!
Old 10-20-2001, 04:30 PM   #2
Registered: Aug 2001
Location: Magic City, USA
Distribution: Ubuntu
Posts: 73

Rep: Reputation: 15
I had this same problem when using IPCHAINS, but once moving to IPTABLES with RH7.1 everything runs great... My home newtwork is all M$ except for the Linux Router (This is sure to change as I can no longer afford to upgrade with M$) If your using the 2.4Kernel I would suggest getting the VPN Masq HOWTO and the IPTABLES HOWTO and read on...

If you just want my rc.firewall to get started with IPTABLES let me know, but there are tons out on the web...


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