Using Divert with ntopng ------------------------ BSD-based operating systems (e.g. pfSense) use the divert interface to send packets to user-space applications such as ntopng. This mechanism is based on a socket interface, so that the communications happen on a local predefined port where packets are received. User space applications such as ntopng can read the traffic and reinject/drop/mark it. Supposing that you want to use port 7777 for the divert mechanism, all you need to do is divert traffic to it. Example: # # Preliminary checks # # http://www.cyberciti.biz/faq/howto-setup-freebsd-ipfw-firewall/ # vi /etc/rc.conf # firewall_enable="YES" # firewall_script="/usr/local/etc/ipfw.rules" # ipdivert_load="YES" # # # kldload ipdivert.ko # ipfw -f flush ipfw add 410 divert 7777 udp from any to any via em0 ipfw add 411 divert 7777 tcp from any to any via em0 ipfw add 412 divert 7777 icmp from any to any via em0 ipfw add 1000 allow ip from any to any The above examble sends to the divert port 7777 all UDP/TCP/ICMP traffic, while letting all the rest of the traffic pass through. Make sure you start ntopng as follows (ntopng will inspect the traffic and let it go through) # ntopng -i divert:7777