On Wed, 9 Mar 2016, David Bass wrote:
Could you do the same with a 1501 byte packet?
I have many times ping:ed with 10000 byte packets on a device that has "ip mtu 9000" configured on it, so it sends out two fragments, one being 9000, the other one around 1100 bytes, only to get back a stream of fragments, none of them larger than 1500 bytes. MTU and MRU are two different things. Regarding jumbo usage, the biggest immediate benefit I can see would be if two ISPs want to exchange tunneled traffic with each other, even if the customer access is 1500, there is definitely benefit in being able to slap an L3 tunnel header on that packet, send it as ~1550 bytes to the other ISP, and then they take off the header again, without having to handle tunnel packet fragments (which tend to be quite resource intensive). -- Mikael Abrahamsson email: swmike@swm.pp.se