Why can't capture rewritten packet

Question

I'm using tcpdump and tcpreplay in ubuntu for capturing packet and resending(with rewriting and openwrt for ap mode in raspberry pi.

My problem is that I cannot capture resent packet.

This is my network :

     A          ---->        B(RPI)           ----------->     C
192.168.0.199      eth0.          wlan0      |             192.168.2.172
               192.168.0.100    192.168.2.1  | 
                                              ------------>     D
                                                           192.168.2.222

I sent packet(using nping) from A to B, and used portforwarding

nping in A :

nping --udp --dest-port 7777 --dest-ip 192.168.0.100

portforwarding in B using iptables :

iptables -t nat -A PREROUTING -i eth0 --dport 7777 -j DNAT --to 192.168.2.222

So, I done here.

And I write this in D

tcpdump -i wlan0 dst port 7777 -w packet.pcap
tcprewrite -i packet.pcap -o packet_rewrite.pcap -D 192.168.2.222:192.168.2.172
tcpreplay -i wlan0 --topspeed packet_rewrite.pcap 

But, in C, I cannot capture modified packet...

tcpdump dst port 7777

I really want to know why i can't...please let me know
and i'm really sorry my explain is not good....

Answer 1

further search.. I captured packets in B (wlan0) Because i edited packet's source mac to my ubuntu wlan mac address... But as before, I cannot capture packets in C... This is captured packets in B

and even replayed packet didn't pass iptables...

I solved!!!!!!!!!!!!!!

I had to change dmac to C's mac address....I was stupid....