I see an error in my squid cache.log that I think is TProxy related, and wanted to post it here to see if anyone had input before posting it to the squid list. The versions of everything I am using is listed below, followed by the error. Software versions: squid-3.HEAD-20080721 iptables 1.4.0 kernel 2.6.25.11 This is part of a WCCP setup with a Cisco router. My iptables setup is: Table: filter Chain INPUT (policy ACCEPT) num target prot opt source destination 1 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 2 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 3 ACCEPT 47 -- 0.0.0.0/0 0.0.0.0/0 4 ACCEPT 47 -- 0.0.0.0/0 0.0.0.0/0 5 LocalFW all -- 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy ACCEPT) num target prot opt source destination 1 LocalFW all -- 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT) num target prot opt source destination Chain LocalFW (2 references) num target prot opt source destination 1 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 2 ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmp type 255 3 ACCEPT udp -- 10.48.33.2 0.0.0.0/0 udp dpt:2048 4 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 5 ACCEPT tcp -- 10.9.7.206 0.0.0.0/0 tcp dpt:22 state NEW 6 ACCEPT tcp -- 10.2.5.100 0.0.0.0/0 tcp dpt:22 state NEW 7 ACCEPT tcp -- 10.9.7.206 0.0.0.0/0 tcp dpt:10000 state NEW 8 ACCEPT udp -- 10.2.5.100 0.0.0.0/0 udp spt:161 9 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:8080 10 ACCEPT tcp -- 10.9.7.206 0.0.0.0/0 tcp dpt:10000 11 REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited Table: mangle Chain PREROUTING (policy ACCEPT) num target prot opt source destination 1 DIVERT tcp -- 0.0.0.0/0 0.0.0.0/0 socket 2 TPROXY tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 TPROXY redirect 0.0.0.0:3128 mark 0x1/0x1 Chain INPUT (policy ACCEPT) num target prot opt source destination Chain FORWARD (policy ACCEPT) num target prot opt source destination Chain OUTPUT (policy ACCEPT) num target prot opt source destination Chain POSTROUTING (policy ACCEPT) num target prot opt source destination Chain DIVERT (1 references) num target prot opt source destination 1 MARK all -- 0.0.0.0/0 0.0.0.0/0 MARK set 0x1 2 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 The squid clients are in the 10.48.1.0/24 subnet, the router is in both the 10.48.1.0/24 and the 10.48.33.0/24 subnet. The squid box is 10.48.33.2, the router is 10.48.33.1. Both IP subnets are seperate layer 2 vlans. In the errors below, 10.48.1.200 is my client test machine. Error with "echo 0 > /proc/sys/net/ipv4/ip_nonlocal_bind": 2008/07/22 12:57:05| IPInterception.cc(137) NetfilterInterception: NF getsockopt(SO_ORIGINAL_DST) failed: (11) Resource temporarily unavailable 2008/07/22 12:57:05| IPInterception.cc(171) NetfilterTransparent: NF getsockopt(IP_TRANSPARENT) failed: (92) Protocol not available Error with "echo 1 > /proc/sys/net/ipv4/ip_nonlocal_bind": 2008/07/22 13:01:50| IPInterception.cc(137) NetfilterInterception: NF getsockopt(SO_ORIGINAL_DST) failed: (11) Resource temporarily unavailable 2008/07/22 13:01:50| IPInterception.cc(171) NetfilterTransparent: NF getsockopt(IP_TRANSPARENT) failed: (92) Protocol not available 2008/07/22 13:01:54| commBind: Cannot bind socket FD 30 to 10.48.1.200:5675: (98) Address already in use 2008/07/22 13:01:54| comm.cc(997) commResetFD: bind: (98) Address already in use