When a Gen-3-based port and a Gen-2-based port are attached to a LAG SAP (also referred to as mix-and-match LAG), configuring scheduler mode for the LAG SAP is required because it is used by Gen-2 ports, but it is ignored by the Gen-3 port.
For more information, see the ‟LAG Support on Third-Generation Ethernet Adapter Cards, Ports, and Platforms” section in the 7705 SAR Interface Configuration Guide.