Chris Robertson: After installing the devel kernel: yum -y install kernel.i686 kernel-devel.i686 I now have the netfilter header file: [root@squid0 ~]# find /usr/include -name netfilter_ipv4.h /usr/include/linux/netfilter_ipv4.h However I still get errors: checking for linux/netfilter_ipv4.h... no checking for linux/netfilter_ipv4/ip_tproxy.h... no Are these just related to the --enable-linux-tproxy option? I also see this: Linux (Netfilter) Transparent Proxy enabled Amos Jeffries: I'd like to use the lastest verion of TPROXY, that matches my Fedora netfilter version. >Those are squids tests for v2.2 support (due to the --enable-tproxy >option). If thats the right version of TPROXY you wanted, AND you have >patched your kernel correctly prior to building squid, I'll take a look >and see why its failing. I will try the configure without this option as I would like to tuse TPROXY4+ I guess. >If you meant to build with the new TPROXYv4+ support, you will need the >3-HEAD (3.1 beta) code. The -tproxy option only needed to enable v2.2 >support there. So what you are saying is that if I want to use TPROXYv4+, I need to grab the beta code from here: http://www.squid-cache.org/Versions/v3/HEAD/ if I want to get TPROXYv4+? Additionally I do not need to add the -tproxy option when I run the configure? R