Another fantastic feature that Cisco StackPower technology offers is that it stores sufficient power to help bring up the MCU of the Cisco WS-C3850-24XS-S series of switches. The result this brings is that it adds resiliency to the stack of switches. During the processes required for the budgeting of the IOS Software, there is a step where switches in the stack are all lined up in a ring topology. During that process, without the need to have any service interruption occurring to the current operational Power Stack, new members can be added to the existing Power Stack, and it can be either Star or Ring. It’s also vital to understand that either of the two currently existing Rings can’t merge without the possibility of the service interruption occurring to either of the two rings.

Therefore, enough care is required to make sure that the ring is only broken one time and not more than that, and this is to make sure that there is no service interruption occurring in every case.

 Zero-footprint redundant power supply


Before looking further into the zero-footprint RPS, you need to understand what it is in the first place. Zero-footprint RPS is the capability to offer redundancy without the necessary demand for having an actual RPS.

The function of a Power Stack


The power stack is the one that finds the members of the stack helping at the starting of the process where the members exchange informational messages that helps in figuring out exactly how much power is available in the stack and also sets up the necessary steps to set the priorities.

The power stack then collects all the power available in the stack from the different sources that have them. It then helps subtract the amount of power from the power pool equivalent to the enormous power supply in the stack. But don’t mistake it for the fact that it subtracts the power supply itself. It doesn’t do that, and neither does it turn off any of the power supply.

This might get a little confusing, but it can better understand with a simple example. The example goes like this; a power stack forms when a particular cable helps connect the switches. It results in forming a closed ring that is quite similar to the topology present in the stack of the Cisco StackWise.

In a ring topology, there can be four switches only that can be a part of a power stack, and as for the number of switches that can be a part of the star topology, they are eight switches. The cables that help form the power stack have current flowing through them, and this current feed the switches which are in dire need of power or complement the requirements of the power of the switches in the stack. It is an entirely safe system because there are plenty of circuit breakers present that are spread all around the printed circuit board. It is done like that to help cut off the entire system itself or the current to various components in the system, whichever seems like the most plausible option.

Cisco PowerStack Cables


The cables of the Cisco PowerStack are flexible, and they are incredibly thick, which accounts for their sturdiness. They carry data signals and the power of course to provide a channel for communications between the Cisco WS C3850 24XS S series of switches of the power stack.

The XPS and the Cisco PowerStack cables have colored bands on the ends that help understand and determine what the connector can plug into. Both the cables are also keyed.

Guidelines for connecting the cables


There are specific guidelines that need to be followed thoroughly before connecting the switches to the power stack. These guidelines are as follows:

The switch power stack can include eight switches in a star topology with the XPS and only up to four switches in a ring topology.

The size of any power-supply module is optional, and the switch’s size is significant before connecting the cables to the switches. The 1100W power-supply module is longer than the other modules because it’s 1.5 inches long. And if you’re attaching the cable retention cable clip, it can extend to a maximum of 3 inches. To make it all the easier for yourself to cable the switches, you can also stack the Cisco Catalyst 3850 series of switches and the same power-supply modules.

When it comes to the cable’s length, it mostly depends on the kind of configurations you have. You’ll need cables of varying sizes when you have a different configuration. If you do not give the detail of the length of Cisco StackPower, then typically only the 0.3-meter cable is provided, but you can also get a 1.5-meter cable when you ask them to give you that.