0

When Linux receives a UDP packet originating from a sender having a LAN source IP, will Linux put the source MAC address of this packet along the source IP address into the ARP cache table?

  • Have you tried it? – Stephen Kitt Sep 25 '17 at 14:58
  • I'm about to try it. – thomas Sep 25 '17 at 15:00
1

I tried Linux 4.9 and the answer in this case is no. I crafted an UDP packet with an artificial IP address and MAC address combo, which was received by the Linux-under-Test and displayed correctly by netcat. No ARP entry was created (also no incomplete one) and Linux did not send any ARP request regarding the artificial IP address.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.