[ipxe-devel] ipxe hangs on boot when receiving a jumbo frame

[Michael Brown]

On 20/04/15 09:31, ahmed wrote:
> We have spent some days trying to debug this problem with no success.
> we hope to find some help here.
> As indicated on the mail subject, we have three servers A, B, and C on
> the same broadcast domain.
> A and B communicate via a multi-cast protocol with frame of size 9000
> (real packet size less than 256 but they are padded with 0 to MTU size).
>
> When booting C receive those packets  as a result it timeout on boot, we
> have on debug message with unknown protocol 0000.
> We suppose that only part of the payload is read and then either an
> overflow screw up everything or the remaining part of the payload is
> considered as a new packet and mess up things.
> We have also tried decreasing MTU from 9000 (in A,B) to 4000 and 2000
> but still the same error.
> C boots only when we bring back A,B MTU to 1500

Which driver are you using (according to "ifstat")?

Michael