White Papers

● The new stack master uses its own startup and running configurations to synchronize the configurations on the new stack
members.
NOTE: Adding a new unit that is powered on and has stack groups configured is the same as merging two stacks (refer to
Adding a Stack Unit). If the new unit is configured 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 reboots and is
added as a member switch.
Split a Stack
To split an S5000 stack, unplug the port cables between member units at any time: while the stack is powered on or off and
when the units are online or offline.
Each portion of the split stack retains the startup and running configuration 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 standby units, it is unaffected 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 Dell Networking OS
elects a new standby.
● If one of the new stacks does not receive either the master or 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 previous stack master comes back online, it becomes a member unit.
● Prevent the stack master or stack unit from rebooting after a failover.
CONFIGURATION mode
redundancy disable-auto-reboot stack-unit
This command does not affect 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 commands.
If you try to reset the stack master, an error message displays: Reset of master unit is not allowed.
● Reload a stack unit from the master switch.
EXEC Privilege mode
reset stack-unit unit-number
● Reload a member unit from the unit itself.
EXEC Privilege mode
reset-self
● Reset a stack-unit when the unit is in a problem state.
EXEC Privilege mode
reset stack-unit unit-number hard
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Stacking