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-   -   dnsmasq with Firestarter? (

sancho 06-26-2006 06:04 PM

dnsmasq with Firestarter?

I run both a laptop and desktop in my room and would like to hook both into the network, but I have only one ethernet connection into the room. So what I've done is added a second NIC to the desktop, and then have the laptop connected via a crossover cable to the desktop. The desktop is then connected to a Linksys router, which connects everything to the Internet. The setup looks like this:


                                        [Desktop PC]
(INTERNET) <---> [Linksys Router] <---> eth0:      [Laptop]
                                        eth1: <---> eth0:

I realize that Firestarter has the ability to setup the 'dhcp3-server' to provide DHCP capabilities on the internal interface, which works just fine. However, I would like to use 'dnsmasq' instead because of its smaller footprint and ability to answer DNS queries for the internal network. I have dnsmasq running just fine on the machine and, as long as the firewall isn't started, it correctly assigns the laptop an address and answers DNS queries. The problem is when I start the firewall with Firestarter: when I do this, the laptop never gets assigned an IP address.

It would seem that Firestarter is blocking DHCP requests on the internal interface (eth1) but it works fine using the "built in" dhcp3-server interface.

Any ideas on what I need to do to get this thing running with dnsmasq?


acid_kewpie 06-27-2006 01:12 AM

wsell unless there is anything more blatant you would just unblock udp port 67 and 68.

personally though you don't seem to have really picked the best way to do what you want... you should actually buy a stupidly cheap switch and use that to plug both devices into the linksys subnet, and let that router serve dns and dhcp for you. unless there's a good reason not to, that's much simpler.

sancho 06-27-2006 06:48 PM

Unblocking the ports which DHCP uses was the first thing I did, but oddly that didn't work: The firewall starts and dnsmasq runs, but the laptop doesn't get an IP. Stop the firewall and try again, and the laptop gets its IP immediately. I made sure the other DHCP server wasn't running in either case.

In fact, there is a way that's both cheaper than buying a new switch and more simple than setting up dnsmasq: I could simply setup a static IP on the laptop and call it a day. However, I use NetworkManager on the laptop to automagically handle all network activity, and it unfourtinately doesn't do static IPs. I added the NIC to the desktop because it was a spare I had laying around. I know I'm not the first Linux user out there who'd prefer not to pay for things that he can legitimately get for free. ;)

Ashrack 07-01-2006 03:40 PM

its a bug between FIRESTARTER and DNSMASQ!!!
Check this link for a better explanation. And on the link a workarround is posted but it doesnt work 4M. Tell me if it does 4U

acid_kewpie 07-01-2006 03:45 PM

nice catch, wouldn't have eer got there myself!

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