Several phenomena were observed during link up testing:
The cable used is ACC OSFP 800G-2x400G QSFP112. The OSFP end is connected to an Arista 7060X6 switch, and the QSFP112 end connects to the ConnectX-8 NIC.
The link fails to come up when using a ConnectX-8 NIC. However, with all configuration parameters unchanged, swapping to a ConnectX-7 NIC brings the link up normally.
We would like to inquire what changes were introduced from CX7 to CX8 that cause this compatibility difference. Switches equipped with TH5 chips exhibit identical issues.
Troubleshooting logs captured on the NIC side are as follows:
plaintext
Troubleshooting Info
Status Opcode : 2
Group Opcode : PHY FW
Recommendation : Negotiation failure
After configuring the port to Force Speed 400G, the physical link shows linkup status.
Additionally, comparative testing shows that the link comes up normally on ConnectX-8 NIC when using AEC cables.