I am trying to get a transparent proxy working via WCCP V2 and am having an issue. I am running Red Hat 5 fully updated. IP Forwarding is enabled, RP_FILTER is disabled, the firewall is disabled. The kernel on Red Hat 5 is 2.6.18 which is supposed to have the patched version of ip_gre. My iptable entry is built to port map traffic on port 80 to 3128 and I have tested that it is working. The gre tunnel is online and I can see traffic coming through the tunnel to port 80. The SYN packet comes in but no SYN ACK ever leaves. I placed a laptop on the same subnet as the Linux machine and pointed my default route to the Linux machine. The transparent proxying worked properly,I could surf the Internet, and I saw the requests in my access.log file so I am confident that Squid is configured properly for transparency. The device that is using WCCP V2 to send the traffic to my cache sees that the cache is there and shows no errors. ifconfig gre1 show lots of RX packets but no TX. Any ideas? Thanks!
