Administration: Stack Management
Overview
59 Cisco 500 Series Stackable Managed Switch Administration Guide Release 1.3
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An example of eight devices connected into a stack is shown in the following:
Stack Architecture (Chain Topology)
A stack provides the following benefits:
• Network capacity can be expanded or contracted dynamically. By adding a 
unit, the administrator can dynamically increase the number of ports in the 
stack while maintaining a single, logically-managed device. Similarly, units 
can be removed to decrease network capacity.
• The stacked system supports redundancy in the following ways:
- The backup unit becomes the master of the stack if the original master 
fails.
- The stack system supports two types of topologies: chain (see “Stack 
Architecture (Chain Topology)”and ring (see “Stack in Ring 
Top olo gy”). In ring topology, if one of the stack ports fails, the stack 
continues to function in chain topology (see Stack Topology).
- A process known as Fast Stack Link Failover is supported on the ports in 
a ring stack to reduce the duration of data packet loss when one of the 
stack ports link fails. Until the stack recovers to the new chain topology, 
the stack port that is currently down, loops back the packets that were 
supposed to be sent through it, so that the packets arrive at their 
destination using the remaining stacking links. During Fast Stack Link 
failover, the master/backup units remain active and functioning.