Netfilter IPv6 packet duplication to alternate destination

modulename: nf_dup_ipv6.ko

configname: CONFIG_NF_DUP_IPV6

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>Network packet filtering framework (Netfilter)
└─>The IPv6 protocol
└─>IPv6: Netfilter Configuration
└─>Netfilter IPv6 packet duplication to alternate destination
In linux kernel since version 4.1 (release Date: 2015-06-21)  
This option enables the nf_dup_ipv6 core, which duplicates an IPv6
packet to be rerouted to another destination.

source code: