How to find out PoE output levels on a switch/port?

I have a slightly different kind of question for a change. If you wanted to find out how much power is being supplied by PoE ports on a Cisco Catalyst switch, how would it be done? I'd like to know the total amount that each switch is putting out and, if possible, how much each PoE port on the switch is putting out? I know I can keep plugging devices in until it won't power any more, but I'd like some method that will allow for better planning and not leave me looking like a complete nut. For the record, the switches are still running IOS 12 - with the exact version dependent upon the device, with one exception. One of the switches is running 16.3.1, because it was brand new this summer. Most of the switches are 2960's.

If the method is dependent upon an IOS version, I'd still like to hear the method and know which version of IOS supports the parts that allow it to work correctly. If the method requires custom pollers, I will have many more questions to ask and will not feel bad about looking somewhat dense, because I know others will learn from my questions and the answers to them.

Thanks in advance and I will be asking Cisco much the same kind of questions.

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ctlswadmin

Doug,

The best way to go about this might be custom pollers. Here's something quick I threw together to see if this is what you had in mind, I might be off on my approach here.

Tested this on 11.5.3, should work on the .12 release.

Select NodeName,SensorDisplayName,SensorValue,SensorUnit
From APM_HardwareSensorAlertData
Where CategoryName LIKE '%power%'

d09h

Are you polling this MIB already (custom MIB polling)?

CISCO-POWER-ETHERNET-EXT-MIB

If nothing in that MIB reports the total power across all ports, perhaps a poller transform would be helpful (or SQL query to achieve the same result).

This list looks promising: ftp://ftp.cisco.com/pub/mibs/v2/CISCO-POWER-ETHERNET-EXT-MIB.my

If you have any hunches from the above URL, you may be able to confirm with an SNMPwalk, or correlation of CLI output, or TAC case.

jhandberg

The built in EnergyWise reports may also have some of this information as long as you are collecting the data.

lynchnigel

Hi there

hopefully this will help, quite an old thread though

Cisco PoE Monitoring

FormerMember

ok. I'll have to try that and see if that helps.

FormerMember

I don't think we're polling it, but I'm not certain. What would I check on Solarwinds or the switches to see if it is turned on and the stuff it needs to see is enabled?

FormerMember

I don't believe we are currently collecting the EnergyWise information. I don't remember seeing anything in the config about it anyway. I looked at several of the switches (via List Resources) and the EnergyWise box is not checked.

A related question to the original one. When I ssh'd into several of the switches and had it show the PoE information for the ports, it gave exact information on any Cisco device lugged into it (IP Phone, wireless AP), but on anything else, it was reporting it as 'Ieee PD' and having it as pulling full power (15.4 w). Some of those devices (mostly IP video cameras) would've had little or no traffic in their field of view, they are tuned to go to lower fps and lower quality in that instance, but go back to full fps and quality if something enters it's field of view. I would expect the cameras to pull less power when they are slowed down, but there is no signs of it from the switch inquiry. Do I misunderstand something about the way the PoE works on the switch or is the switch unable to lower the power requirements because it is not a Cisco device and is listed as a generic IEEE af type device (what the Ieee PD indicates if I understood the IOS 12.2 documentation correctly)?

FormerMember

It may be old, but it did give me some useful information to think about while I figure this all out. I wasn't aware that you could have more than one poller attached to a device, but I may have missed it in the documentation.

I'm also going to presume that it (or something very similar) will work with NPM 12.0.1?

jhandberg

I think if it is reporting and IEEE level, they always get full power. The connected device would have to be able to negotiate power levels for that to change. Negotiations are usually on power up though. This device may just "get" full 15.4W possible port output because it didn't ask for a different level. We had that happen at my old job with security cameras attached. They just didn't negotiate a level and got full power all the time.

As for EnergyWise, I do recall enabling basic EnergyWise commands on all of my Cisco switches at the old job so they would report, and that may be why the reports worked for me. I didn't do anything else special that would enable those if I recall correctly.

d09h

Before trying to create a poller, perhaps SNMPwalk 1.3.6.1.4.1.9.9.402 or SNMPwalk the whole tree and look at that section. See if anything can be learned from it. If so, there would be benefit in creating a poller.

FormerMember

Ok. So it would appear that the switch is reporting as designed. I guess I need to go through the systems doc on the cameras and see if they can communicate a need to adjust power level by talking to the switch. I also get to go through the IOS doc to figure out what I need to enter into the config files to turn on EnergyWise on the switches (if anything).

Now I'm wondering if I need to look at the pollers that Solarwinds is currently using to see the cameras. They are registering as PoE and an IP device, but that is all. We monitor connectivity through Solarwinds and use the vendor software for actually looking at video. It may all be able to talk in a better manner than it is now (almost not at all).

FormerMember

Sounds like a good suggestion, whether it finds more itself or gives me more information for the custom poller.

FormerMember

I can report that of the two switches I have enabled EnergyWise upon, I am getting information from them to Solarwinds. I'm not getting all of the information that I would like to see, but I know must be there - since it is displayed if I "show power inline" while logged into the switches. I haven't done any real tweaking of reports yet either, so I will see how that goes. It may also be that the default pollers do not collect the information and they may need to be tweaked.

d09h

When working with multiple universal device pollers, pulling all the data into a Node Details or into a summary type of page seemed daunting initially. Then I realized the benefit in reports that match against common portions of OID (for example 1.3.6.1.4.1.9.9.402.*) or by poller grouping similar to here (How to Set Up Multi-Column Table With Custom Device Poller ). I don't know if that URL is too old to be relevant, but the grouping of pollers made ugliness of SQL joins unnecessary.

FormerMember

There are extra fields under the OID in the database that may be what I want to see, but I haven't built the report to get the info and I don't know that it is being collected by the existing stock poller. When I looked, it didn't seem that all the stuff I want to see is grabbed for display. While max power is pulled or can be inferred by the way things are identified (0-4, 4 being unknown), I didn't see where it was pulling the actual draw currently or max draw for the device. I know the data is out on the switch, but I have to find all the config options on the switch to turn on and then get it collected and in a useful place for Solarwinds to let me put it in a report/resource.

When I get it figured out, I will intend to help the next person out by posting commands to activate it and how I got things moved around and into the report/resource.