Hi, this is my scenario router(linux eth0).........eth2(lusca)..............eth1(wan) policy routing done for clients to reach to lusca (clients on private ips 172.16.x.x) lusca can ping clients and internet tproxy redirection done as per : iptables -t mangle -N DIVERT iptables -t mangle -A DIVERT -j MARK --set-mark 1 iptables -t mangle -A DIVERT -j ACCEPT iptables -t mangle -A PREROUTING -p tcp -s 172.16.10.97 -m socket -j DIVERT iptables -t mangle -A PREROUTING -p tcp --dport 80 -j TPROXY --tproxy-mark 0x1/0x1 --on-port 3129 ip rule add fwmark 1 lookup 100 ip route add local 0.0.0.0/0 dev lo table 100 squid.conf http_port 127.0.0.1:3128 http_port 0.0.0.0:3129 tproxy but browsing give error : Invalid Request Some aspect of the HTTP Request is invalid. Possible problems: Missing or unknown request method Missing URL Missing HTTP Identifier (HTTP/1.0) Request is too large Content-Length missing for POST or PUT requests Illegal character in hostname; underscores are not allowed squid logs [21/Apr/2013:13:04:42 +0530] "GET error:invalid-request HTTP/0.0" 400 3334 TCP_DENIED:NONE works fine on iptables dnat and transparent directives -- Nettlynx Networks