Troubleshooting Unit Replacement Issues

The unit replacement process is intended to replace one unit with a clean unit of exactly the same model without entering any command. Unit replacement is not designed to discover new units. Refer to Replacing Stack Units in Stacking deployment guidelines for more information.

Check the following items when you experience unit replacement issues.

• The replacement unit is a clean unit (does not contain a startup-config.txt file).
• The replacement unit running configuration does not contain the stack enable command.
• The replacement unit running configuration does not contain the stack disable command.
• The configurations for the stack ports on the active controller match the physical connections to the unit.
• Only one unit is being replaced at a time. If the active controller detects multiple new units, it issues warning messages.
• The clean unit must match only one reserved stack unit configuration. The active controller issues warning messages if the new unit matches multiple units.
• The console of the new unit displays a warning message if the unit receives unit-replacement packets when it does not qualify for unit replacement.