I successfully configure tproxy all the steps. (Patching Centos, Patching iptables, Building squid). And also WCCP configuration with L4 WCCPv2. When I trying check gre0 tunnel with any packet flow but don’t found any request.

My error showed………………………………….
[root@heldas]# tcpdump -i gre0
tcpdump: WARNING: arptype 778 not supported by libpcap - falling back to cooked socket
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on gre0, link-type LINUX_SLL (Linux cooked), capture size 96 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel

My iptables script is……………………………

#/bin/bash
/sbin/iptables -t mangle -N DIVERT
/sbin/iptables -t mangle -A PREROUTING -p tcp -m socket -j DIVERT
/sbin/iptables -t mangle -A DIVERT -j MARK --set-mark 1
/sbin/iptables -t mangle -A DIVERT -j ACCEPT
/sbin/iptables -t mangle -A PREROUTING -p tcp --dport 80 -j TPROXY --tproxy-mark 0x1/0x1 --on-port 3129

My Physical connectivity structure is ……..
Internet cloud to Cisco core router to Juniper firewall to Distributed Cisco router to Core Cisco switch to TPROXY 

Please give me a solution …

Thanks
Engr.Mohammad
Monzur Alam
Network & System Admin
Grameen CyberNet Ltd.
Dhaka, Bangladesh