I'm trying to simulate a communication between two PC.
PC1 (192.168.19.11) is sending data using unicast to PC2
To simulate after this communication, I've made a cap file with
ethereal on PC2.
My first problem is when data are larger than MTU (1500 bytes), it
happens that I don't have all IP fragments in the capture file.
If you have an idea where can it come from?
I think it's just a problem of capturing with ethereal (may be it
My second problem is when I want to replay the capture with tcpreplay:
Between PC3(192.168.18.99) and PC4(192.168.18.20)
First I change the MAC addresses:
tcprewrite --enet-dmac=00:55:22:AF:C6:37 --enet-smac=00:44:66:FC:29:AF
When I open the output.cap file, UDP checksum are correct
Then I change the IP adresses:
tcprewrite --srcipmap=192.168.19.11/32:192.168.18.99/32 --
tcprewrite --dstipmap=192.168.19.10/32:192.168.18.20/32 --
When I try to open outfile3.pcap, wireshark tells me that UDP checksum
incorrect for fragmented packet.
Then I force to fix checksum:
tcprewrite --fixcsum --infile=outfile3.pcap --outfile=outputFinal.pcap
The last command doesn't work for fragmented packet.
When I try to replay outputFinal, PC4 doesn't see data superior to MTU
even probably because of the UDP CHECKSUM INCORRECT.
I've tried to disable checksum of my NIC with ethtool but I still
doesn't receive packet.
Any help will help me.