| Description | This object specifies the information about the mode of the
power stack.
Power-sharing mode: All of the input power can be used for
loads, and the total available power appears as one huge power
supply. The power budget includes all power from all supplies.
No power is set aside for power supply failures, so if a power
supply fails, load shedding (shutting down of powered devices or
switches) might occur. This is the default.
Redundant mode: The largest power supply is removed from the
power pool to be used as backup power in case one of the other
power supplies fails. The available power budget is the total
power minus the largest power supply. This reduces the available
power in the pool for switches and powered devices to draw from,
but in case of a failure or an extreme power load, there is less
chance of having to shut down switches or powered devices. This
is the recommended operating mode if your system has enough
power.
In addition, you can configure each mode to run a strict power
budget or a non-strict (loose) power budget. If the mode is
strict, the stack power needs cannot exceed the available power.
When the power budgeted to devices reaches the maximum available
PoE power, power is denied to the next device seeking power. In
this mode the stack never goes into an over-budgeted power mode.
When the mode is non-strict, budgeted power is allowed to exceed
available power. This is normally not a problem because most
devices do not run at full power and the chances of all powered
devices in the stack requiring maximum power at the same time is
small. |