Allied Telesis AT-8000GS/24, AT-8000GS/POE manual Stacking Overview, Stacking Ring Topology

Chapter 3: Stacking

Stacking Overview

Stacking Ring Topology

Stacking provides multiple switch management through a single point as if all stack members are a single unit. All stack members are accessed through a single IP address through which the stack is managed. The stack can be managed using the following interfaces:

ˆWeb-based Interface

ˆSNMP Management Station

ˆCommand Line Interface (CLI)

Devices support stacking up to six units per stack, or can operate as stand-alone units. During the Stacking setup, one switch is selected as the Stacking Master and another stacking member can be selected as the Secondary Master. All other devices are selected as stack members, and assigned a unique Unit ID.

Switch software is downloaded separately for each stack member. However, all units in the stack must be running the same software version.

Switch stacking and configuration is maintained by the Stacking Master. The Stacking Master detects and reconfigures the ports with minimal operational impact in the event of:

ˆUnit Failure

ˆInter-unit Stacking Link Failure

ˆUnit Insertion

ˆRemoving a Stacking Unit

ˆThis section includes the following topics:

ˆ“Stacking Ring Topology,” next

ˆ“Stacking Chain Topology,” next

ˆ“Stacking Members and Unit ID,” next

ˆ“Removing and Replacing Stacking Members,” next

ˆ“Exchanging Stacking Members,” next

Stacked devices operate in a Ring topology. A Ring topology is where all devices in the stack are connected to each other forming a circle. Each stacked device accepts data and sends it to the device to which it is physically connected. The packet continues through the stack until it reaches the destination port. The system automatically discovers the optimal path on which to send traffic.

Most difficulties in Ring topologies occur when a device in the ring becomes non-functional, or a link is severed. In a stack, the system

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