mipsbe boards only allow max MTU of 1520???

Hardware MikroTik hardware general
1

Am I doing something wrong, or do the Mipsbe boards only allow a maximum size of 1520 MTU, even then they are set for Gigabit.

Thanks.

ke6hpz

2

It depends on the board, the chips, etc.

If you take a look at

http://wiki.mikrotik.com/wiki/Manual:Maximum_Transmission_Unit_on_RouterBoards

You will see the various MTU sizes of different boards.

Regards
Alexander

3

It is basically related to hadware switching chips.
And it is not the only hardware design flaw. Think about having 5 ports but only 2 real “gigabit” interfaces in the SoC of a RB450G…

4

why exactly that is a flaw? most of the time configuration is ether1 as wan and rest of the ports switched, of some (2 or 3 are in switch group) of them. Also on fast links i rarely see high bandwidth for extended periods of time. Of course it is good to know with a bit of explanation.

5

There should be enough CPU resource on most boards to do an EOIP tunnel (router to router) which can handle much larger MTU.

6

well, most RB’s/switches support Jumbo frames for 1GBE up to 9k MTU.
not sure about “large send” feature, support :confused: