Deployment Guide

Stacking

An Aggregator auto-congures to operate in standalone mode. To use an Aggregator in a stack, you must manually congure it using the

CLI to operate in stacking mode.

In automated Stack mode, the base module 40GbE ports (33 and 37) operate as stack links and it is xed.

In Programmable MUX (PMUX) mode, you can select either the base or optional modules (ports 33 — 56). An Aggregator supports a

maximum of six stacking units.

Stacking provides a single point of management for high availability and higher throughput.

NOTE: Internal ports cannot be used for stacking.

NOTE: Prior to conguring the stack-group, ensure that the stacking ports are connected and in 40G native

mode.

Supported Modes

Standalone, PMUX, VLT, Stacking

Topics:

• Stacking Aggregators

• Stacking Port Numbers

• Stacking in PMUX Mode

• Conguring a Switch Stack

• Conguring the Uplink Speed of Interfaces as 40 Gigabit Ethernet

• Merging Two Operational Stacks

• Verifying a Stack Conguration

• Troubleshooting a Switch Stack

• Upgrading a Switch Stack

• Upgrading a Single Stack Unit

Stacking Aggregators

A stack of Aggregators operates as a virtual chassis with management units (primary and standby) and member units. The Dell Networking

operating software elects a primary (master) and secondary (standby) management unit. The forwarding database resides on the master

switch; the standby unit maintains a synchronized local copy. Each unit in the stack makes forwarding decisions based on their local copy.

The following example shows how you can stack two Aggregators. The Aggregators are connected to operate as a single stack in a ring

topology using only the 40GbE ports on the base modules.

Stacking 241