I want to setup tproxy in my local net. I studied your howto: http://wiki.squid-cache.org/Features/Tproxy4 but I don't understand how to adapt it to my setup. I'm using squid-3.1.0.13_beta iptables-1.4.3.2 and kernel 2.6.30 from a gentoo distribution. I have a linear net topology: internet <----> 192.168.1.1 adsl router <----> 192.168.1.12 proxy server 192.168.0.12 <----> 192.168.0.13 local_client this is the routing table for the client: local_client ~ # route -en Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 127.0.0.0 127.0.0.1 255.0.0.0 UG 0 0 0 lo 0.0.0.0 192.168.0.12 0.0.0.0 UG 0 0 0 eth0 and this one for the proxy server: proxy_server ~ # ip route list table all local default dev lo table 100 scope host 192.168.1.0/24 dev eth1 proto kernel scope link src 192.168.1.12 192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.12 127.0.0.0/8 via 127.0.0.1 dev lo default via 192.168.1.1 dev eth1 broadcast 192.168.0.255 dev eth0 table local proto kernel scope link src 192.168.0.12 broadcast 192.168.1.0 dev eth1 table local proto kernel scope link src 192.168.1.12 broadcast 127.255.255.255 dev lo table local proto kernel scope link src 127.0.0.1 local 192.168.0.12 dev eth0 table local proto kernel scope host src 192.168.0.12 broadcast 192.168.0.0 dev eth0 table local proto kernel scope link src 192.168.0.12 broadcast 192.168.1.255 dev eth1 table local proto kernel scope link src 192.168.1.12 local 192.168.1.12 dev eth1 table local proto kernel scope host src 192.168.1.12 broadcast 127.0.0.0 dev lo table local proto kernel scope link src 127.0.0.1 local 127.0.0.1 dev lo table local proto kernel scope host src 127.0.0.1 local 127.0.0.0/8 dev lo table local proto kernel scope host src 127.0.0.1 proxy_server ~ # ip rule 0: from all lookup local 32765: from all fwmark 0x1 lookup 100 32766: from all lookup main 32767: from all lookup default this is my squid configuration: proxy_server ~ # grep -v ^# /etc/squid/squid.conf|grep -v ^$ acl manager proto cache_object acl localhost src 127.0.0.1/32 acl to_localhost dst 127.0.0.0/8 acl localnet src 10.0.0.0/8 # RFC1918 possible internal network acl localnet src 172.16.0.0/12 # RFC1918 possible internal network acl localnet src 192.168.0.0/16 # RFC1918 possible internal network acl SSL_ports port 443 acl Safe_ports port 80 # http acl Safe_ports port 21 # ftp acl Safe_ports port 443 # https acl Safe_ports port 70 # gopher acl Safe_ports port 210 # wais acl Safe_ports port 1025-65535 # unregistered ports acl Safe_ports port 280 # http-mgmt acl Safe_ports port 488 # gss-http acl Safe_ports port 591 # filemaker acl Safe_ports port 777 # multiling http acl Safe_ports port 901 # SWAT acl purge method PURGE acl CONNECT method CONNECT http_access allow manager localhost http_access deny manager http_access allow purge localhost http_access deny purge http_access deny !Safe_ports http_access deny CONNECT !SSL_ports http_access allow localnet http_access allow localhost http_access allow localhost http_access deny all http_port 3128 http_port 3129 tproxy hierarchy_stoplist cgi-bin ? cache_dir diskd /var/cache/squid 50M 16 256 coredump_dir /var/cache/squid refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern -i (/cgi-bin/|\?) 0 0% 0 refresh_pattern . 0 20% 4320 shutdown_lifetime 2 seconds visible_hostname proxy_server this is my iptables conf: proxy_server ~ # iptables -t mangle -L -n Chain PREROUTING (policy ACCEPT) target prot opt source destination DIVERT tcp -- 0.0.0.0/0 0.0.0.0/0 socket TPROXY tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 TPROXY redirect 192.168.1.12:3129 mark 0x1/0x1 Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination Chain DIVERT (1 references) target prot opt source destination MARK all -- 0.0.0.0/0 0.0.0.0/0 MARK xset 0x1/0xffffffff ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 the following are commands to build this conf: 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 -m socket -j DIVERT iptables -t mangle -A PREROUTING -p tcp --dport 80 -j TPROXY --tproxy-mark 0x1/0x1 --on-port 3129 --on-ip 192.168.1.12 ip rule add fwmark 1 lookup 100 ip route add local 0.0.0.0/0 dev lo table 100 echo 1 > /proc/sys/net/ipv4/ip_forward but all this does not works. the client does not ping out of 192.168.0.* : local_client ~ # ping 192.168.1.1 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data. ^C --- 192.168.1.1 ping statistics --- 87 packets transmitted, 0 received, 100% packet loss, time 85999ms squid works, but only for internet bots which are looking my home apache server: proxy_server ~ # tail -n 89 /var/log/squid/access.log -n1 1250664301.462 0 66.249.67.133 TCP_DENIED/403 3771 GET http://cloc3.dyndns.org/index.html/doku.php/22_dicembre_2008/problema4? - NONE/- text/html That's stupid: I want squid for the local users, not for remote hosts. Where I'm falling?