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Someone point out what obvious thing I'm missing here... I'm just setting up a router/firewall at work, and everything works lovely apart from I can't ping through the firewall. I'm using iptables, the forward policy is set to 'drop' and I've got an explicit rule to allocal ICMP through so I've got this:
Code:
$IPTABLES -P FORWARD DROP
$IPTABLES -F FORWARD
$IPTABLES -A FORWARD -i $EXTIF -o $INTIF -m state --state ESTABLISHED,RELATED -j ACCEPT
$IPTABLES -A FORWARD -i $INTIF -o $EXTIF -m state --state ESTABLISHED,RELATED -j ACCEPT
$IPTABLES -A FORWARD -i $INTIF -o $EXTIF -m icmp -p icmp -j ACCEPT
$IPTABLES -A FORWARD -i $EXTIF -o $INTIF -m icmp -p icmp -j ACCEPT
<<lots more rules>>
But alas no ICMP echo requests or replys get forwarded.
You could try deleting the "-m icmp" on the forward chain, filter outbound for "-m state --state new established related" and in for related. If you're filtering types, the type you want to allow out and back in is echo request, IIRC.
In general when TS'ing fw scripts I'd go for "catch all" logging rules, restart the script and see what's getting dropped off a chain.
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