Alcatel-Lucent 6850-48 Hardware Manual

Managing OmniSwitch 6850 Series Stacks

Roles Within the Stack

OmniSwitch 6850 Series Hardware Users Guide

page 4-9

In order to provide effective management module redundancy, all OmniSwitch 6850 Series stacked 
configurations dynamically assign a backup, or secondary, management module during the boot process. 
OmniSwitch 6850 Series stacks use two different methods for selecting the secondary switch. These meth-
ods are:

• Stacking connection to the primary switch

• Saved slot number

By default, the switch that is connected to the primary switch’s stacking port A is automatically assigned 
the secondary management role. This applies to stacks on which there is no preassigned slot information—
i.e., there is no boot.slot.cfg file present in any switch.

For more information on using the stacking connection to the primary switch to determine the secondary 
management module, refer to the diagram below:

Note. For information on dynamic slot numbering for idle elements within the stack, refer to 

.

Four OmniSwitch 6850 Series switches are 
stacked and connected via stacking cables, as 
shown. All switches are currently powered off. 
None of the switches have preassigned slot 
numbers—i.e., there are no boot.slot.cfg files 
present. The user powers on all switches in the 
stack in close succession and the stack begins 
the boot process.

By default, the switch connected to the 
primary’s stacking port A is automatically 
assigned the secondary management role. 
The secondary switch is dynamically 
assigned slot number 2.

When the elements in the stack come online, 
the switch with the lowest MAC address is 
given the primary management role and is 
dynamically assigned slot number 1. 

00:d0:95:b2:3c:8e

00:d0:95:b2:2a:ab

00:d0:95:b2:1c:ff

00:d0:95:b2:5b:8d

Idle

Idle

Primary