I have 2 identical switches (Cisco SG550X-48P) and I want to stack them using a fiber link across 2 buildings on our campus. I logged into one of them and went to stack management and tried to select the stacking port to use however when I try to save and reboot at the bottom I get an error saying I have to select at least 2 ports to configure stacking. I do not understand why this is. I only want to stack these 2 switches in a chain topology from port TE1 to TE1 on each switch. I do not have capacity to assign another stack port as the main switch that is already in use is using the rest of the TE ports. Why would i need 2 ports on each switch to configure a stack?