Per-outlet metered PDUs... options?

[djbon2112]

I've got 8 servers: one C6100 chassis with dual PSUs, three machines with dual PSUs, and one machine with a single PSU. I'm looking for options to determine the per-port power of each of these, along with my other networking gear. The downside is that none of my devices are "new"/advanced enough to provide real power output in either the OS or IPMI level. I've pretty much settled on getting two PDUs that can do per-port metering?/monitoring? to get accurate results and know, for example, which machine caused my UPS load to spike 20% for 2 minutes.

The problem as my slash-question there implies, is navigating the marketing BS and inconsistent naming of this feature. So, I'm hoping some of the more datacenter-aware denizens of STH can help point me towards the available options!

My conditions are fairly limiting however: 120V only, 20A source plugs (to connect to a SmartUPS 2200), and 0U/vertical to fit at the back of my custom-build rack. Without breaking the bank. (TripLite has one perfectly matching my conditions... for $1200 USD each new... a little too much for my blood.)

So, what do you use? What would you recommend? Has anyone achieved the same thing without a PDU? I'm curious to know how you track your per-machine power!

 

[Patrick]

We use the APC AP8441 PDUs with this feature but they are for 208V and also in the $1200 range without environment monitors.

What you could do, and it would be a bit ugly, is use cheaper entire strip PDUs and just plug one system into each and then monitor for that. If you had 20+ devices that would be impractical, but you could roll through with say 4 of these PDUs and try that way.

I have seen a cheap system where you basically use AC clamps to monitor. I cannot remember the name of that.

Unfortunately, what you want just costs $1200 these days.

 

[cactus]

You might look into seeing if any of the smart plugs(WeMo, TP-Link HS110, etc.) allow you to log.
I bought some mPowers to do this ~4 years ago. Don't even remember what happened to those... Ubnt EOL'd all the mFi stuff though.

 

[Blinky 42]

Is your custom built rack 40U or greater in height? You may be able to find used 120V per-outlet metered units somewhere but there is far more selection in the 200/208/240 volt sector. Not a lot of volume on the 120V side so less selection and bad prices.

I have not used these personally but I have seen them one is a while - Eaton refers to them as "MO" for metered outputs
http://powerquality.eaton.com/Products-services/Backup-Power-UPS/Eaton-ePDU-G3-Metered-Outlet.aspx

APC / Schneider has them as Metered by outlet (I think always with switching by outlet)
Metered-by-Outlet with Switching Rack PDU - APC - United States

You found the tripp lite one it looks like.

Other hacky ways to do it depend on how long term you want it to be nd level of adventure
- Kill-a-watt's on power cords of suspect devices.
- Use one of the metered input / normal metered options that watches the input to the whole PDU and just plug one device into the PDU (or pair of PDUs at a time to monitor the usage that way).
- Rig up your own by opening a basic PDU, add current transformer per outlet and a decent ADC with your favorite Raspberry Pi like board for measurement and logging.

 

[djbon2112]

Thanks guys, you've pretty much confirmed what my own research has - these aren't cheap :-(

> - Rig up your own by opening a basic PDU, add current transformer per outlet and a decent ADC with your favorite Raspberry Pi like board for measurement and logging.

This is likely going to be the solution I go with - I'm already using 12-port linear metal power bars so I can probably hack transformers into them, assuming of course they're not just a busbar inside, and assuming I can find a good way to link them all up. *fingers crossed*

I'd do the one-PDU-per-server, but then the entire back of the rack would be filled with PDUs! ;-) The rack could handle it (it works out to ~6ft of internal vertical space) but I'm more concerned about cost than anything.

 

[K D]

There are used/refurbished ones on ebay for about 100-200 bucks. Not sure how good these models are.

APC Schneider Electric Switched Rack AP8961 24-Outlets 5.7kW PDU C13, C19 | eBay.

Also Tripp-Lite has metered PDUs that seem reasonably priced.

https://smile.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=aps&field-keywords=metered+pdu

 

[djbon2112]

There are used/refurbished ones on ebay for about 100-200 bucks. Not sure how good these models are.

APC Schneider Electric Switched Rack AP8961 24-Outlets 5.7kW PDU C13, C19 | eBay.

Also Tripp-Lite has metered PDUs that seem reasonably priced.

https://smile.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=aps&field-keywords=metered+pdu

They're all per-PDU metering though, not per-outlet. It's such a shame too - I almost bought two of these cheaper ones not realizing all the marketing BS about the difference. I'm glad I checked the spec page!

 

[K D]

That's good to know. I just needed to remove a 1U PDU and was looking at vertical ones that will not take up an RU. Metered/Monitored was a bonus. Like @Blinky 42 mentioned, I just use a kill-a-watt for individual servers when needed.

 

[Kybber]

One option might be to split the cables going from the PDU to your devices and mount one of the cheap Sonoff Pow units on each cable. This gets you a remote controlled power switch and power meter for ~$11 each. Apparently there is no API for logging outside the app, but it should be simple enough to switch to another firmware.