Re: vlan with higher MTU (jumbo frame) than underlying Ethernet interface

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Fri, Sep 07, 2012 at 11:21:11AM -0700, Erik Fair wrote:
> NetBSD's documentation doesn't say explicitly: can one have a vlan interface 
> with a jumbo frame MTU (e.g. 9000), on top of an Ethernet interface which 
> supports jumbo frames, but whose MTU (1500) has not be adjusted up?

No, I think the underlying interface needs to have the hightest MTU of all
vlans.

> 
> The goal would be to use jumbo frames between consenting hosts on a switch 
> that supports jumbo grams, but segregate the traffic by VID (and IP address) 
> such that a jumbo-supporting host won't send jumbograms to a non-supporting 
> host by default.

But you can have another vlan(4) interface with 1500 MTU

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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