Administrator Guide

• All the units in the losing stack go for a reboot and then merge with the winning stack that has the stack master.
• If there is no unit numbering conict, the stack members retain their previous unit numbers. Otherwise, the stack master assigns
new unit numbers, based on the order in which they come online.
• The new stack master uses its own startup and running congurations to synchronize the congurations on the new stack
members.
NOTE: Adding a new unit that is powered on and has stack groups congured is the same as merging two stacks (refer to
Adding a Stack Unit). If the new unit has been congured with a higher priority than the current stack master, it
becomes the new stack master and the stack reloads. If the new unit does not have a higher priority than the master
switch, it is added as a member switch.
Splitting a Stack
To split an MXL 10/40GbE switch stack, unplug the stacking cables between member units at any time: while the stack is powered
on or o and when the units are online or oine.
Each portion of the split stack retains the startup and running conguration of the original stack.
For a stack that is split into two smaller stacks, each with multiple units:
• If one of the new stacks receives the master and the standby units, it is unaected by the split.
• If one of the new stacks receives only the master unit, the master switch retains its role and a new standby is elected.
• If one of the new stacks receives only the standby unit, it becomes the master in the new stack and the Dell Networking OS
elects a new standby.
• If one of the new stacks receives neither the master nor the standby unit, the stack is reset so that a new election takes place.
Managing Redundant Stack Management
To manage the redundancy behavior in a stack, use the following redundancy commands.
• Reset the current stack master and make the standby unit the new master.
EXEC Privilege mode
redundancy force-failover stack-unit
A new standby is elected. When the former stack master comes back online, it becomes a member unit.
• Prevent the stack master from rebooting after a failover.
CONFIGURATION mode
redundancy disable-auto-reboot stack-unit
This command does not aect a forced failover, manual reset, or a stack-link disconnect.
• Display redundancy information.
EXEC Privilege mode
show redundancy
Resetting a Unit on a Stack
To reload any of the member units or the standby in a stack, use the following reset commands.
If you try to reset the stack master, an error message displays:
% Error: Reset of master unit is not allowed.
To rest a unit on a stack, use the following commands.
• Reload a stack-unit.
EXEC Privilege mode
reset stack-unit unit-number
Stacking
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