Policy and Lowest Common Denominator Stacking

When devices are stacked that have different capacities, we sink to the lowest common level of capacities and functionality when possible. If the stack already has an existing configuration that exceeds the new lower capacity policy will disallow the ports on the new unit to become policy enabled.

Note

Note

In some cases policy capacities of a device have been determined to be so low that they are deigned non-useful for any practical policy deployment. In these cases the ports on the device are never allowed to become policy enabled.

The following algorithm is used to determine the lowest common denominator when stacking:

(A) More Capable device(s)
(B) Less Capable device(s) 

- (A) is running and (B) is added

   If (A) is currently using less or equal resources to the maximum 
   capacity (B) provides.
       - Policy will reduce the system maximum capacity
        to match (B). 
   If (A) is currently using more resources than the maximum capacity (B) provides.           
        - Policy will not be enabled on the ports of (B).
        - A message will be printed that indicates the condition to the     
          customer. If the resources being used by (A) are reduced to less or equal the maximum capacity of (B)
        the ports on (B) will become policy enabled. A message will be printed that indicates the condition to the customer and thereafter every
        5 minutes as the condition exists. If the resources being used by (A) are reduced to less or equal the maximum capacity of (B)
        a message will be printed that indicates this slot can fully function with policy pending a
        reboot of (B). This message will repeat every 5 minutes until (B) is
        rebooted.               - (B) is running and
        (A) is added      ? The
        system maximum capacity will continue to match (B)           
        - If (B) is removed (A) will revert to its higher capacity.                  - (A) and (B) brought
        up at the same time.      ? The
        system maximum capacity will be the lower capacity of (B)- If (B) is removed
        (A) will revert to its higher maximum capacity.