slackware 10.2/2.6.17.8 pc using rc.firewall script from easy firewall generator, two nics, cable modem connects to nic1, nic2 connects to a switch, other pc's connect to the switch

everything worked fine for like 24 hours then internet access stopped, lan access still works, rebooted pc, reset the switch, no affect

seems like a nameserver problem but i checked the dns ip's and they havent changed

ssh logs in slow with this happening

what can i use or do to diagnose what might be wrong and where

i can provide additional information as necessary, thanks

Try calling your internet service provider

if i connect cable modem to win pc i can get on internet

this seems a bit like before i spoofed the mac address, is it possible for isp to unspoof?

comcast needs my mac address for their service, the nic is built in to the motherboard, i spoofed that mac address on the router pc, is it possible theres a mac address conflict? as i stated before everything worked great then stopped, thanks

Suggestion, re-install Distro with the actual MAC Address. After the reboot and settings applied as YOU prefer, then tweak the firewall/IPTables or other filtering. Because there are so many files with the MAC Address association, the fresh install will lessen the complications down the road towards YOUR system being setup YOUR way. Solid reading here...http://en.wikipedia.org/wiki/Iptables