Scenario 3 - Manually Configuring a Three-member Stack in a Ring Topology

If you are connecting units that have been individually configured for stacking and want unit IDs to be assigned based on physical sequence, you may want to configure the stack manually.

Complete the following steps to configure a three-member stack in a ring topology using the manual configuration process. In this example, device 1 is the active controller, and device 2 is the standby controller. Unit 3 boots up as a member, based on the configured priorities for units 1 and 2.

  1. Power on the devices. Do not connect the stacking cables at this point.
  2. Assign a priority of 255 to unit 1 and a priority of 240 to unit 2 using the priority command. You do not have to assign a priority to the third unit.
  3. Enter the stack enable command on each device.

    In this example, device 1 is the active controller, and device 2 is the standby controller.

    Unit 1 

    device# configure terminal
device(config)# stack unit 1
device(config-unit-1)# priority  255
device(config-unit-1)# stack  enable
Enable stacking. This unit actively participates in stacking
device(config-unit-1)# write memory
Write startup-config done.
Flash Memory Write (8192 bytes per dot) .Flash to Flash Done.
device(config-unit-1)# end

    Unit 2 

    device# configure terminal
device(config)# stack suggested-id 2
device(config)# stack unit 1
device(config-unit-1)# priority  240
device(config-unit-1)# stack enable
Enable stacking. This unit actively participates in stacking
device(config-unit-1)# write memory
Write startup-config done.
Flash Memory Write (8192 bytes per dot) .Flash to Flash Done.
device(config-unit-1)# end

    Unit 3 

    device# configure terminal
device(config)# stack suggested-id 3
device(config)# stack enable
Enable stacking. This unit actively participates in stacking
Write startup-config done.
Flash Memory Write (8192 bytes per dot) .Flash to Flash Done.
device(config-unit-1)# end
  4. Connect the devices in a stack topology. The active controller retains its ID. The rest of the units are assigned unique ID numbers depending on the sequence in which you connected them.

    For more information about cabling the devices, refer to the stacking overview for the device and the appropriate hardware installation guide.

    Note: This method does not guarantee sequential stack IDs if you do not configure the optional stack suggested-id command on each standalone unit. If you want to change stack IDs to make them sequential, you can use stack interactive-setup. Refer to Changing stack unit IDs with stack interactive-setup.
    Note: You can configure the stack suggested-id command in a standalone unit before using the stack enable command to cause the unit to join the stack. A unit is assigned the suggested ID if no other unit in the stack has that ID.
Parent topic: Stack Construction Methods