Recently I have configured na Iptables Firewall with transparent proxy (squid) on a Debian RC3.01 machine. The machine is a pentium 3, with 600MHz and 196 MB of RAM. The script is working fine, there is no problem with the rules, but a strange thing happens. Sometimes the internet connection suddenly stops. The external interface stop responding. To solve the problem, sometimes I only restart the interface (ifdown eth0; ifup eth0) bot sometime it doesn't work and the only solution is to reboot the machine. I have already checked /proc/net/ip_conntrack, the logs and restarted the firewall script, but I can only reestablish the service rebooting the machine.
