Reference Guide

858 | Stacking
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Stacking S5000 Switches
A stack of S5000 switches operates as a virtual chassis with management units (master and standby) and
member units. The FTOS operating software elects a primary (master) and secondary (standby)
management unit; all other units are member units. The forwarding database resides on the master switch;
all other stack units maintain a synchronized local copy. Each unit in the stack makes forwarding decisions
based on their local copy.
Figure 47-1 shows an example of how you can stack four S5000 switches and the role played by each
switch in the stack. The S5000 switches are connected to operate as a single stack using only 10GbE ports
on Ethernet pluggable modules. Note that the four 10GbE ports in a stack group on one switch are
connected to the four 10GbE ports in a stack group on a peer stacked switch in order to maximize
throughput. For more information, see Supported Stacking Topologies.
Figure 47-1. Four Stacked S5000 Switches
Stack Management Roles
The stack elects the management units for the stack management:
• Stack master: primary management unit
• Standby: secondary management unit
The master holds the control plane and the other units maintain a local copy of the forwarding databases.
From Stack master you can configure:
• System-level features that apply to all stack members