46 Dell PowerConnect 55xx Systems User GuideFILE LOCATION: C:\Users\gina\Desktop\Checkout_new\Maintenance Projects\DellContax\sources\CxUGStacking.fmD E L L C O N F I D E N T I A L – P R E L I M I N A R Y 1 0 / 3 0 / 1 3 - F O R P R O O F O N LYStack OverviewThe PowerConnect 5500 Stacking feature provides multiple switchmanagement through a single switch, so that all units in the stack are treatedas if they were a single switch. All stack members are accessed through themanagement IP address, through which the stack is managed.Each switch is a member in a stack, although the stack may consist of only asingle switch.Up to eight units can be stacked.This section covers the following topics:• Stack Operation Modes• Stacking Units• Stack TopologyStack Operation ModesAll stacks must have a Master unit, and may have a Master Backup unit. Allother units are connected to the stack as members (slaves).A unit in the stack can be in one of the following modes:• Stack Master — Runs the fully operational software of a switch. Inaddition, it runs configures and manages all other units in the stack. Allprotocols run in the context of the Master unit. It is responsible forupdating and synchronizing the Master Backup.The Stack Master detects and reconfigures the ports with minimaloperational impact in the event of:Unit failureInter-unit stacking link failureUnit insertionUnit removalWhen the Master unit boots, or when inserting or removing a stackmember, the Master unit initiates a stacking discovering process.
