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Why Stack Ethernet Switches?
Stacking Ethernet switches reduces the network administrator’s total cost of ownership. The cost of maintaining the
network is decreased because there are fewer devices to manage, and the network uptime is increased with built-
in redundancy.
Figure 1 shows two ways to deploy Ethernet switches at the access layer. In each case four switches are
connected to a Cisco Catalyst 6509 Switch. The deployment scenario on the left shows four switches that are
colocated in the same wiring closet, but are not stacked. Each standalone switch on the left has two uplinks to the
distribution layer switch that are combined in an EtherChannel group. The four switches on the right are stacked
together with FlexStack (FlexStack links show in red). The stack has four uplinks to the distribution layer switch.
Because FlexStack supports EtherChannel grouping of Ethernet interfaces across the stack members, the four
uplinks are grouped together into a single EtherChannel group. All the benefits of EtherChannel grouping are
retained when switches are placed into a stack.
Figure 1. Comparison of FlexStack and Nonstacked Configurations
Stacking Ethernet switches provides the network administrator with three major operational benefits:
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Single point of management: All switches in the stack are managed as one.
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Built-in redundancy and high availability: The high-speed FlexStack connections provide redundant
communication for each stack member to every other member.
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Scalability to fit network needs: Installation of a new switch to the stack is easy. As the need for additional
access ports grows, adding a new switch to an existing stack is easier and faster than adding a new
standalone switch to the network.