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Jumbo frames (even with DEF BufferSize changed) are still split up

Open quickbreach opened this issue 8 years ago • 2 comments

After applying the recommended change in the "Limitations" section of README.rst and changing DEF BufferSize to 9000 and compiling from the source, any packets received which are greater than 1500 bytes are continued to be split into multiple packets before being passed to the callback function of the NetfilterQueue object.

Kali 2.x rolling All interfaces have a MTU of 9000

quickbreach avatar Jun 20 '17 17:06 quickbreach

If you watch the traffic with tcpdump, matching on a similar pattern to what you set up to send traffic into your queue, does it show the packets > 1500 bytes or so being received or sent?

mattfox avatar Jun 21 '17 03:06 mattfox

I've confirmed with tcpdump that my machine is receiving frames greater than 1500 bytes long (attached screenshot shows two packets of 3021 bytes being received). Both of these packets were split up, and each piece was passed to my callback function separately - instead of each packet as a whole.

image

quickbreach avatar Jun 21 '17 20:06 quickbreach