These commands might help troubleshoot this issue as they check various aspects of the connectivity between the edge switch and the core switch, such as Layer 3 reachability, Layer 2 adjacency, LACP configuration and status, VLAN trunking configuration, and interface status. Reference: https://www.arubanetworks.com/techdocs/AOS-CX_10_04/CLI/GUID-8F0E7E8B-0F4B-4A3C-AE7F-0F1B5A7F9C5D.html