Alcatel-Lucent OmniSwitch 6250-24M User Manual page 115

Managing OmniSwitch 6250 Stacks
Important Note. For management module redundancy to work effectively, the software on all switches
operating in the stack must be synchronized at all times. Refer to
page 6-37 for more information.
Primary
Secondary
Idle
Idle
!
Offline
Secondary
Idle
Idle
Offline
Primary
Secondary
Idle
Idle
Primary
Secondary
Idle
Redundant Management Module Failover (Three or More Switches)
OmniSwitch 6250 Hardware Users Guide
1
A stack of four OmniSwitch 6250 switches is operating
normally. The stack consists of a primary module, sec-
ondary module, and two elements operating in idle sta-
tus. (The software on all elements in the stack is
synchronized.)
2
The primary management module in the stack fails or is
taken offline (e.g., powered off or rebooted by the user).
3 The switch operating as the secondary management module
immediately takes over the primary role. Meanwhile, the
adjacent switch—previously operating in idle status—now
assumes the secondary management role.
4
If the switch that failed or was taken offline comes back
online, it will assume an idle role in the stack. In other
words, it will act essentially as an NI module in the virtual
chassis, passing traffic via its Ethernet.
June 2012
Roles Within the Stack
"Synchronizing Switches in a Stack" on
page 6-5