Hi ALL,

I want to setup Transpaent Proxy on the box running iptables Firewall.

With iptables, I have given below rules.

iptables -F INPUT iptables -F OUTPUT iptables -F FORWARD iptables -F -t nat iptables -F -t mangle

#Enabling ip forwarding echo "1" > /proc/sys/net/ipv4/ip_forward

#enable syn cookies (prevent against the common 'syn flood attack') echo "1" > /proc/sys/net/ipv4/tcp_syncookies

#do source validation by reversed path echo "1" > /proc/sys/net/ipv4/conf/all/rp_filter

#Enable tracking mechanism /sbin/modprobe -a ip_conntrack_ftp ip_nat_ftp

iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT iptables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

iptables -A INPUT DROP iptables -A FORWARD DROP iptables -A OUTPUT DROP

in addition to that, There are many rules , ALL work fine.

in squid.conf file, I have added below rules,

http_port 3128 cache_mem 64 MB cache_dir ufs /var/spool/squid 100 16 256 cache_access_log /var/log/squid/access.log cache_log /var/log/squid/cache.log cache_store_log /var/log/squid/store.log

httpd_accel_host virtual httpd_accel_port 80 httpd_accel_with_proxy on httpd_accel_uses_host_header on

And, Then, I did below command.

iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 3128

But, When I browse Internet , request will not get ridirected to 3128 port. So I can not use squid as a Transpaent Proxy.

Where have I gone wrong?

I reffered to below URL. http://www.tldp.org/HOWTO/TransparentProxy.html#toc2

Pls help me.