Re: using non-default MTU for some hosts

[Mikhail Teterin <mi+dragonflybsd@xxxxxxxxxxxxxxxxx>]

Matthew Dillon wrote in <200410292118.i9TLITRX095178@xxxxxxxxxxxxxxxxxxxx>:

> :Is there a way to use a non-default MTU to talk to some of the hosts on
> :the local network? Thanks!

>     Yes, though it must still be smaller then the MTU assigned to the
>     outgoing network interface.

>     You can use the 'route' command to create routes to particular target
>     hosts or target networks and specify various parameters for that
>     route, including the mtu.

Thanks for the prompt response! I was hoping, it would also work the other
way... Can you give a quick example, please? Let's say, two BSD-hosts: "mi"
and "pandora" have the jumbo-frame cards and want to use them fully. The
rest of the network -- say 172.21.128/20 -- can only use the 1500-long
frames.

What are the commands to enter on both machines? I figure, I must start with
something like `ifconfig em0 mtu 8000' on each one, but then, how do I tell
them, that they should limit the mtu to 1500 in almost all cases? Thanks
again!

 -mi