Internet Connection Sharing - How To?Forum: Networking Topic: Internet Connection Sharing - How To? started by: waspbloke Posted by waspbloke on Jan. 02 2006,14:03
Hello, first thing to say is that I am a Linux virgin - well not quite, I have kissed a few but never climbed into bed with any. Until DSL opened my eyes to the joy of 50mb distros - now I can't stop fiddling.My problem is: I have a W2Kpro with 3 NICs NIC1=red/internet, DHCP NIC2=green/LAN, Static IP 192.168.0.1/24 NIC3 unused My brother has a laptop 1 NIC: NIC1=green/LAN, Static IP 192.168.0.42/24 gw 192.168.0.1 dns1 and dns2 are set to my external dns When in windows it works as you'd expect. When I boot my machine with DSL i want to be able for brother's laptop to seemlessly connect to the internet as before. I have read this forum to bits and the wiki and so many other Linux (networking/IP masqerading/IP forwarding) how-to sites and am frankly stuck!!! I think it was YoLinux site that seemed to sugguest that all I need do is set my static IP, enable IP forwarding and add a couple of routes. I have tried all ways but no matter what i do, the 192.168.0.42 laptop remains unpingable, it can't ping my DSL machine and no ICS happens. I have IPtables extensions loading from myDSL at boot, tried the rc.firewall extension (no joy) and using the rc.firewall setup script from their site - says everything was done properly but still no traffic. I suspect the problem is the routing as when I look at my W2Kpro route table it has a bunch of 224.0.0.0 and 255.255.255.255 stuff (11 routes and 1 default gw), whereas my DSL routes are way more minimal with only 3 or 4 routes. Now I am no networking guru but am capable of creating good solid small office networks and such in windows. Linux seems to be the OS of choice for doing routing/firewalling and the fact that my pre-configured coyote-linux floppy fw/router got on with and did exactly what i wanted makes me think something simple is missing in my DSL config/install. There's an awful lot of ambiguity about how to setup a static IP addy on my eth1 LAN adapter aswell - I currently have a line in bootlocal.sh: ifconfig eth1... etc. Some sites suggest putting scripts in various locations within /etc. What to do? Please please help! Posted by waspbloke on Jan. 03 2006,20:54
Right-o, sorted that out by switching the LAN to eth2. Still not entirely happy...At boot up i see eth0 eth1 eth2 come alive and broadcasting...which fails (no dhcp server) for eth1 & eth2. my bootlocal.sh then flushes iptables, sets up my iptables rules, enables ipforwarding, invokes ifconfig eth2 as my LAN gateway - which then goes and dies by the time the desktop loads and I need to ifconfig eth2 x.x.x.x again to bring it back. from there on it works question is having read around - there are 2 ways it seems to 'hardwire' my inet adapters; 1. defined in files /etc/sysconfig/network-scrips/ifcfg-eth0 (& -eth1 & -eth2) 2. initialized (as is the loopback) in /etc/network/interfaces Can I use either method to force DSL into accepting my config before it goes off trying to get IP addys from non-existent DHCP servers and how do it? I have tried hacking the ifcfg-eth0/1/2 files in as root and altering the interfaces file but neither method survives a reboot. I have DSL frugal HD install on a 54mb part A, myDSL/backup/opt/home 1Gb part B Somebody must know! Please help, i've only been doing this for 5 days! Posted by Brocc69 on Jan. 03 2006,22:31
I have similar setup working on Xandros...It may work for you!my setup: eth0--> internet eth1--> lan use a crossover cable from eth1 to my laptop. use the program "firestarter" only on the computer with the internet connection. (you may have to "apt-get install firestarter") open a console and "su", enter root password, then "firestarter". in the configure screen, set internet source as eth0. share internet box should be checked with eth1 selected to be the one sharing. start the firewall and all is good. wish ya luck. Posted by botbotdingzip on Jan. 04 2006,11:45
Hi all, I have a similair problem to the first post. Firstly, love the distro. It's all I wanted - a feature rich barebones os to learn from. I'm having some trouble understanding the complexities of setting up a dsl dhcp server similair to what XP has with ICS and a mac bridge. I want to emulate something like the mac bridge that XP has for connection sharing. I need to get this up some how because my GF has a 98 and a XP box that runs off my box, which sadly has XP ICS. Yeah so I don't want XP as the conduit anymore. Any ideas on how to get DSL to fill this niche would be greatly appreciated. Yeah I surfed yo-linux and a quintillion other sites already in self help mode. I'm sure there's other guys and gals out there who have had the same quandary. Posted by Grim on Jan. 09 2006,07:12
The reason why you don't have a DHCP server available in DSL is because you don't have one installed. `apt-get install dhcp dhcp-relay` Go read: < http://www.syrlug.org/contrib/soho-network-p2.html > < http://www.touset.org/projects/howtos/fwhowto/fwhowto.html > and quite possibly: < http://www.aboutdebian.com/proxy.htm > and when you realize that you'll have to recompile the kernel and jump through a bunch of hoops and then it still won't work exactly right, go buy a friggin router. They're like $30US at Wal-Mart. |