I have X520-DA2 cards, and was wondering if 802.3ap KR training is performed over the SFP+ cables (direct attach copper).
In the 82599 datasheet (section 184.108.40.206) it seems to imply that 802.3ap training is performed, as described in section 72.6.10 of 802.3ap-2007.
I wish to confirm this is true.
It would seem to make sense that the same performance optimizations for backplane KR would apply to direct attach (SFP+) copper cables (i hope?)
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