I recently installed my hard drive in a new computer and after some fiddling around I noticed my iptables rules were dropping DNS responses for some reason, turns out they were configured to allow stuff on eth0, but eth8 is used in this computer and everything was being dropped (not just DNS queires). Anyhow, I was using Wireshark concurrently to see if the DNS servers were responding to the queries and found out that they did. But I had just noticed iptables was dropping said packets. How come Wireshark can see the packets if they are being dropped?
Script used to generate the ruleset:
# Flush all rules iptables -F iptables -X # Allow unlimited traffic on loopback iptables -A INPUT -i lo -j ACCEPT iptables -A OUTPUT -o lo -j ACCEPT # Allow incomming traffic from estabilished and related connections iptables -A INPUT -i eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT # Policy: Allow outgoing, deny incoming and forwarding iptables -P OUTPUT ACCEPT iptables -P INPUT DROP iptables -P FORWARD DROP