Stack Unit Replacement

You can replace any stack unit except the active controller with a clean unit of the same model without entering any commands. Discovery and unit replacement are completed in approximately one to two minutes; however, additional time is required to reload the new unit.

To replace a unit, the following are required:

  • The unit being replaced must have a static configuration. Use the show stack command as shown in the following procedures to check for an "S" next to the unit, indicating its configuration is static.
  • The physical modules of the replacement unit must match one and only one provisional configuration, that is, a stored configuration without a physical unit present.
  • The replacement unit must be a clean unit. You can convert a unit to a clean unit using the erase startup-config command followed by the reload command without saving any configuration.

Stack unit replacement is performed for one unit at a time to handle any setup.

Note: Starting with release 08.0.90, connecting the stack units with IDs in ascending or descending sequential order is no longer required.

Unit Replacement Limitations

Starting with release 08.0.90, stack unit replacement does not work in the following cases:

  • Multiple units are being replaced simultaneously. In this case, use stack interactive-setup or stack zero-touch provisioning to discover the stack units.
  • The modules on the replacement unit do not match any provisional configuration.
  • The modules on the replacement unit match more than one provisional configuration.
  • Stack zero-touch provisioning is enabled.