Hello Balazs, Last time I tried tproxy+squid combo [latest available versions]. In genral it worked but some traffic goes from squid "unspoofed" with orginal client addres. When it happens following erros appears [AFAIK due to debug support in Gianni Tedesco's squid patch http://www.scaramanga.co.uk/ ] IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:0837 -> 0809a8c0:e70b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:001d -> 0809a8c0:e70b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:0830 -> 0809a8c0:eb0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:db80 -> 0809a8c0:ec0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:0748 -> 0809a8c0:ed0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:1254 -> 0809a8c0:eb0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:6473 -> 0809a8c0:ec0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:62df -> 0809a8c0:ee0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:7504 -> 0809a8c0:e70b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:4ddc -> 0809a8c0:ee0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:d260 -> 0809a8c0:ec0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:42ad -> 0809a8c0:e70b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:3112 -> 0809a8c0:ee0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:8dec -> 0809a8c0:ec0b IP_TPROXY: error applying NAT mapping, hooknum=4 0c64a8c0:a177 -> 0809a8c0:e70b What reason of error can it be, kernel or squid ? Regards, tw -- PS. I also posted this info to Gianni.