Roles Within the Stack Managing OmniSwitch 6450 Stacks
page 7-10 OmniSwitch 6450 Hardware Users Guide September 2015
Secondary Management Module Selection
In order to provide effective management module redundancy, all OmniSwitch 6450 stacked configura-
tions dynamically assign a backup, or secondary, management module during the boot process. OmniS-
witch 6450 stacks use two different methods for selecting the secondary switch. These methods are:
• Stacking connection to the primary switch
• Saved slot number
Using the Stacking Connection to the Primary Switch
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:
Secondary Management Module Selection Using the Stacking Connection to the Primary Switch
Note. For information on dynamic slot numbering for idle elements within the stack, refer to “Idle Module 
Role” on page 7-12 and “Slot Numbering” on page 7-20.
Four OmniSwitch 6450 switches are stacked 
and connected via stacking cables, as shown. 
All switches are currently powered off. None 
of the switches have preassigned slot num-
bers—i.e., there are no boot.slot.cfg files pres-
ent. 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 second-
ary management role. The second-
ary switch is dynamically assigned 
slot number 2.
1
2
3
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. 
A B
A B
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
Secondary - Slot 2
(Primary - Slot 1)