3-23 
port of another interface module, that is, two ports at the same side cannot be connected, as shown 
in 
Figure 3-31.  
Figure 3-31 Cable connections in a switch stack system in the non-aggregate mode 
 
 
z  When 2-port interface modules are adopted in a stack with ports operating in the aggregation mode, 
ports of MOD 1 can only be connected to ports of MOD 2, and the locations of the ports of the 
interface modules are not limited.  
Figure 3-32 Cable connections in a switch stack system in the aggregation mode 
 
 
z  1-port interface modules do not support port aggregation. When 1-port interface modules are 
connected for a stack, the port of MOD 1 can only be connected to the port on MOD 2, as shown by 
callout 1 in 
Figure 3-33; when a 1-port interface module is connected to a 2-port interface module 
for a stack, the port of MOD 1 can only be connected to the right port of the 2-port interface module, 
as shown by callout 2 in 
Figure 3-33.