configuration suggestion

ecks · n00b Joined: 27 Feb 2007 Posts: 64

I need some advice on what I need to configure for my situation. I have a laptop and a home computer, and my home computer has two NICs. My network at school won't let me use two computers for one ethernet plug, and does not allow routers or anything else. I know that I can make it possible to connect my laptop through my computer to the internet, and have been trying to set up iptables for the past couple of weeks. Do I really need iptables for this? Can I enable some option to add a route so that anything incoming from nic1 can outgo to nic2 and vice versa, with no kind of filtering. Will I be able to achieve this by tunneling? Since I use one interface for dhcp, will it be possible to do this:
config_eth0=("dhcp")
config_eth1=( "192.168.1.1/24" )
routes_eth0=( "default via eth0" )
Please let me know what other options I have available besides iptables?

Bones McCracker · Veteran Joined: 14 Mar 2006 Posts: 1611 Location: U.S.A.

http://www.gentoo.org/doc/en/home-router-howto.xml

ecks · n00b Joined: 27 Feb 2007 Posts: 64

I finally got iptables working by reinstalling everything from scratch and using genkernel rather than the manual one. I had to similarly enable the same options, but this time as modules, and it finally worked, now I have iptables working. Since I would like to have my laptop setup through DHCP, i installed dnsmasq on my comp and that worked too. Since I just wanted to see if everything is working after all this time, I decided to not muddle for now with the iptables syntax and install firestarter. That worked pretty well, however I could still not get DNS, it worked only if I input the IP address of google.com in a browser. For some reason, even though dnsmasq is supposed to provide a DNS server, it doesnt for me. I simply pointed my DNS server to be the one that I get DNS for my server, and that worked fine. Once I setup iptables through firestarter, i figure I can just unmerge it and save the current iptables configuration. Well, when I came back the next day, I turned on my laptop and couldn't get an ip address. After reinstalling dnsmasq, and restarting firestarter, I finally turned iptables off, and it worked fine. I guess that means that something is wrong with iptables, it blocks off dhcp requests after it is turned on. Here is the iptables generated by firestarter:

Bones McCracker · Veteran Joined: 14 Mar 2006 Posts: 1611 Location: U.S.A.

Yes, you should be able to.

It's been a long time since I messed with iptables. As I recall, there are other firewall utilities that might be more suited to router configuration than firestarter, although probably few as user-friendly. You should also check your kernel configuration and /etc/sysctl to make sure you do not have any of the networking functionality disabled that is needed for your desktop to function as a router.

Since your "LAN" only consists of one computer, it might be easier and more efficient to use a static IP address. If your laptop has a utility to store and switch between multiple "locations" (network configurations), you can store that static IP address and also the dns information.