To capture packets on an HPE Aruba CX switch and view the output remotely in real-time, the best practice is to use a mirror session that forwards traffic to a remote device running a packet analyzer such as Wireshark. ERSPAN (Encapsulated Remote Switched Port Analyzer) allows the mirror traffic to be encapsulated in GRE and sent over an IP network to a remote monitoring station. This method ensures full packet capture with no local resource constraints and provides full visibility to the analyst.

Option B (using tcpdump on the switch) only provides summarized or limited capture locally.

Option C (mirroring to another switch port) only allows local monitoring and does not provide remote real-time viewing.

Option D (mirror to CPU and then use tshark) is less efficient and may be resource-intensive on the switch.

Therefore, configuring ERSPAN to a remote Wireshark host is the recommended and best way.