Question about the RPS 2300

[fdogarcia]

The RPS 2300  

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps7148/ps7130/product_data_sheet0900aecd805bbef6.html

Cost-Effective Solution

• Innovative power architecture delivers a cost-effective RPS that can connect up to six devices and can actively back-up up to two devices simultaneously, thereby reducing the redundant power cost per device.

why does it say "can connect up to six devices and can actively back-up up to two devices simultaneously"???

If I have 3 switches connected, and all 3 of them lose their AC power coming in, will this device continue to operate all 3 switches?

Manuel Garcia

[David Hornstein · Accepted solution]

Hi Manuel,

Yep it says " Innovative power architecture delivers a cost-effective RPS that can connect up to six devices and can actively back-up up to two devices simultaneously, thereby reducing the redundant power cost per device."

You said."If I have 3 switches connected, and all 3 of them lose their AC power coming in, will this device continue to operate all 3 switches?"

So you can have up to six devices connected to the unit, the Redundant Power Supply 2300 (RPS2300)  can only backup two power supply failures at once.

So, as you say in your example you have three switches connected  and all three loose AC power....well if the Redundant Power Supply 2300 (RPS2300) is also on a UPS, the RPS2300 will backup maximum of two power supplies, so only one switch will be down..

But it is designed to backup the POWER SUPPLY hardware and not really the AC power of certain supported switches.  It is a product to backup the Power supply hardware within a switch , and not really  the AC power coming into the switch.

The Redundant Power Supply 2300 (RPS2300) ishould not be thought of as a UPS, it should be thought of as a redundant power supply that will backup,  maximum two power supplies within two switches  at once.

Notice the datasheet that you referred us to show the application where a UPS is used to backup BOTH the RPS2300 and the Swithes.

By the way, the odds of two power supplies failing at once in two seperate switches  is remote.

The probablility of losing three power supplies at once due to hardware faulure within three switches  is very remote.

regards Dave

[fdogarcia]

Hi David

Thanks for your Answer,

It's possible to have other model of RPS can allow the three switches up the switches are cisco WS-C2960-24TT-L

Manuel

[David Hornstein]

Hi Manuel.

I checked out the Q&A  on the RPS2300; URL;

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps7148/ps7130/prod_qas0900aecd805bbf21.html

and found the following chart;

Table 1. Number of Switches Actively Backed Up by the Cisco RPS 2300

	Cisco RPS 2300 Power Supply Configuration
	1 x 750W	2 x 750W	1 x 1150W	2 x 1150W
Cisco Catalyst 3750-E or 3560-E switches with 1150W PS	Not supported	1	1	2
All other supported network devices	1	2	1	2

• 
  

What are the chances of more that two power supplies within your switches  faiing at once...the  MTBF from the datasheet for the WS-C2960-24TT-L is around 46 years.

• 
  

If the WS-C2960-24TT-L are already backed up with a UPS, the purpose of the RPS is as the name suggests, provide a Redundant Power Supply incase a WS-C2960-24TT-L switch power supply fails.

• 
  

I think you are very cautious with the wording of your question as your switches may be  providing  mission critical connectivity.

If these WS-C2960-24TT-L are providing connectivity for your mission critical applications, a UPS is also a great addition to  protect against power fluctuations that directly affect your WS-C2960-24TT-L's and mission critical network.

regards Dave.