hi just got knoppix, and need a little help getting my firewall in to stealth mode on www.grc.com
{its fine at sygate sos}
but at gibson it shows port 68 is open and port 67 is closed and all the other ports are in stealth mode..

i installed firestarter which didn't seem to do much so i then used this line

/sbin/iptables -A INPUT -p tcp --syn -j DROP

which put all but two ports in to stealth mode

any advice on how to stealth these 2 ports ??