#!/bin/sh OPTS="-o Dir::Etc::sourcelist=./sources.test.list -o Acquire::http::timeout=20" # setup unset http_proxy iptables --flush echo "No network at all" ifdown eth0 time apt-get update $OPTS 2>&1 |grep system ifup eth0 echo "" echo "no working DNS (port 53 DROP)" iptables -A OUTPUT -p udp --dport 53 -j DROP time apt-get update $OPTS 2>&1 |grep system iptables --flush echo "" echo "DNS but no access to archive.ubuntu.com (port 80 DROP)" iptables -A OUTPUT -p tcp --dport 80 -j DROP time apt-get update $OPTS 2>&1 |grep system iptables --flush echo ""