I recently inherited some server hardware from work and decided that it could be my main router at home (among other things). Ubuntu 12.04 server installation harware wise goes well and everything is found and working when I boot up.
So I begin with setting up eth1 with DHCP. This works fine and it gets a public IP address from my modem and we have a working internet connection.
Then I set up my other NIC (eth0) as static (192.168.0.1) and this also works fine. I can access it from other computers in the network.
The problems are coming when I am trying to set up a DHCP server with isc-dhcp-server. It seems like it is working and giving the computers IP adresses but after one reboot it stops working.
After the reboot eth1 will get a public ip from the modem but it doesnt have internet access. I have to manually run dhcpcd eth1 to get it to work again. As far as I know I havent made any changes to DNS.
What am I doing wrong? I have never really had problems with this before. :)