Does anybody have the following problem? Affected: IMQ interfaces with --todev target on PREROUTING chain appear only on 2.6.x kernels (2.4.x working good) Counters on PREROUTING chain working good (with iptraf sniffing on any interface), but imq interfaces lost TCP packets which are forwarded from the internet to the network behind router (only TCP; the rest of traffic like icmp, udp is ok). Try to make two imq interfaces on your internet interface and download file (via ftp, www or somtging else), NOT from your internet router but from computer behind NAT (behind router) and then enable iptraf. Because for router traffic everything working fine. your computer --- router (with nat, imq and iptraf) --- imq0, and imq1 --- internet interface --- Internet configuration: iptables -F iptables -X iptables -Z iptables -F -t nat iptables -X -t nat iptables -F -t mangle iptables -X -t mangle iptables -P FORWARD ACCEPT iptables -P INPUT ACCEPT iptables -P OUTPUT ACCEPT iptables -t nat -A POSTROUTING -s $i -o $INTERNET_ETH -d 0/0 -j SNAT --to $INTERNET_IP # Download iptables -t mangle -A PREROUTING -i $INTERNET_ETH -j IMQ --todev 0 # Upload iptables -t mangle -A POSTROUTING -o $INTERNET_ETH -j IMQ --todev 1 ip link set imq0 up ip link set imq1 up