Author: Fabrice MARIE <fabrice@celestix.com>
Status: Works For Me.

This option adds CONFIG_IP_NF_MATCH_NTH, which supplies a match
module that will allow you to match every Nth packet encountered.
By default there are 16 different counters that can be used.

This match functions in one of two ways
1) Match ever Nth packet, and only the Nth packet.
   example:
    iptables -t mangle -A PREROUTING -m nth --every 10 -j DROP
   This rule will drop every 10th packet.
2) Unique rule for every packet.  This is an easy and quick
   method to produce load-balancing for both inbound and outbound.
   example:
    iptables -t nat -A POSTROUTING -o eth0 -m nth --counter 7 \
             --every 3 --packet 0 -j SNAT --to-source 10.0.0.5
    iptables -t nat -A POSTROUTING -o eth0 -m nth --counter 7 \
             --every 3 --packet 1 -j SNAT --to-source 10.0.0.6
    iptables -t nat -A POSTROUTING -o eth0 -m nth --counter 7 \
             --every 3 --packet 2 -j SNAT --to-source 10.0.0.7
   This example evenly splits connections between the three SNAT
   addresses.

   By using the mangle table and iproute2, you can setup complex
   load-balanced routing.  There's lot of other uses.  Be creative!

Suppported options are:
   --every     Nth         Match every Nth packet
  [--counter]  num         Use counter 0-15 (default:0)
  [--start]    num         Initialize the counter at the number 'num'
                           instead of 0. Must be between 0 and Nth-1
  [--packet]   num         Match on 'num' packet. Must be between 0
                           and Nth-1.
                           If --packet is used for a counter than
                           there must be Nth number of --packet
                           rules, covering all values between 0 and
                           Nth-1 inclusively.

