On Thu, Jan 18, 2018 at 7:14 PM, Jared Mauch <jared@puck.nether.net> wrote:
lets say i can send you a 9K packet. If you receive that frame, and realize you need to fragment, then it’s your routers job to slice 9000 into 5 x 1500.
In practice, no, because the packet you sent had the "don't fragment" bit set. That means my router is not allowed to fragment the packet. Instead, I must send the originating host an ICMP destination unreachable packet stating that the largest packet I can send further is 1500 bytes. You might receive my ICMP message. You might not. After all, I am not the host you were looking for. Good luck. Regards, Bill Herrin P.S. This makes Linux servers happy: iptables -t mangle --insert POSTROUTING --proto tcp \ --tcp-flags SYN,RST,FIN SYN --match tcpmss --mss 1241:65535 \ --jump TCPMSS --set-mss 1240 -- William Herrin ................ herrin@dirtside.com bill@herrin.us Dirtside Systems ......... Web: <http://www.dirtside.com/>