Dynamic Power Allocation

The switch uses dynamic power allocation when the amount of available power changes. For example, one power supply is turned on and you add another power supply or two power supplies are turned on and you turn one off. Unlike static power allocation, dynamic power allocation maximizes the number of modules that are turned on.

When using dynamic power allocation, the switch first turns off all modules in the chassis and then turns on the modules for which sufficient power is available. The module in slot 2 (slot 3 if slot 2 contains a redundant supervisor) is turned on first and then each consecutive module for which sufficient power is available. When the switch reaches a module for which insufficient power is available, that module remains turned off, and the switch searches for and turns on the next module for which sufficient power is available.

For example:

1. One power supply fails and the switch has only 700 watts of power available.
• Modules 1 through 10 consume 660 watts.
• Module 11 and 12 each require 50 watts. But module 13 requires only 40 watts.
2. Modules 1 through 10 are turned on and operate normally.
3. Modules 11 and 12 remain turned off.
4. Module 13 is turned on.
5. Modules 14 through 17 remain turned off because all available power is now consumed.