The show arp command displays the ARP table for a specific VRF or all VRFs on the switch. The ARP table contains the IP address to MAC address mappings for hosts that are directly connected to the switch or reachable through a gateway. If the client device is connected to another switch by VSX LAG, the ARP entry for the client device will not be present on the primary switch unless it has communicated with it recently. Therefore, to find the IP address of theclient device, the administrator should run the show arp command on the secondary switch in the VSX pair, specifying the VRF name that contains the client device’s subnet.References:https://techhub.hpe.com/eginfolib/Aruba/OS-CX_10.04/5200-6692/GUID-9B8F6E8F-9C7A-4F0D-AE7B-9D8E6C5B6A7F.html