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Date: Wed, 21 Mar 2018 09:32:41 -0400
From: "Joseph H. Buehler" <jhpb@cox.net>
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Subject: Re: netmap ixgbevf max frame size
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This turned out to be a limitation of the box we are using, there is apparently hardware between the ixgbevf chip and the fiber.

Joe Buehler

> I am unable to send frames larger than 9216 bytes (destination MAC through trailing CRC inclusive) using ixgbevf hardware with latest netmap code (LINUX).
> 
> What is the source of this limitation?  From the chip datasheet it appears that much larger frames are supported.
> 
> There is mention of 9216 in some of the driver source files but as an MTU, the max frame size is larger.
> 
> Joe Buehler
> 
>