Hi aranc, have tested this series, basicly it works, but i get only ~620 Mbits/sec (much more i will need on wan) in tx-mode of r2, rx-mode (iperf3 -c IP -R on r2) gets full 939 Mbits/sec. Both no retransmitts. tried with my laptop which gets 940Mbit/sec in tx mode too...other end is a R2 with 5.15 connected to lan0 (and eth1+aux enabled, dmesg clean so far...for the "kernel log flooded"-comment). maybe gmac1 needs to be tweaked a bit (clock-settings)? can you confirm this with your board? regards Frank