UPS recommendations?

It’s looking like I’m going to be spending some months away from home, so I’m planning on setting up smaller-scale servers in my home away from home–OPNsense router, TrueNAS on a UGREEN NAS, probably a single Proxmox server. Naturally I want a UPS for these devices. And since that’s three separate servers, it’d be nice if that UPS were networkable–and that seems to be the problem; the only networkable UPSs I’m finding on Google are rack-mountable units with four-figure (or higher) price tags. Any suggestions for something that would be reasonably available in .us?

I would suggest CyberPower CP1500PFCLCD PFC Sinewave UPS System plus a CyberPower RMCARD205 for the networking. You could also connect it directly to the router and use NUT for the networked servers; in fact in the case of TrueNAS I would recommend it given the age of the NUT version included.


Ouch, but not nearly as bad as the rack units I’ve seen. But a bit of an incentive to figure out how to use NUT for this application…

It is actually the same card that is used in their rack units, so one reason that I have been looking at getting one at some point is that it will let you turn the unit back on remotely after a power event causes the ups to shutdown. Not sure how relevant this would be for your use case though.

@dan What are the requirements?

If I read this correctly it will be a single computer running Proxmox, true? And you need a single UPS.

I don’t understand (due to my lack of knowledge) what a NIC connection brings you. Is it remote power on and some sort of monitoring to toss you an email if the UPS has certain status conditions?

Can you use NUT as @dak180 mentioned?

I’m sure there is some reason you have, I just don’t see it yet.

Three computers: Proxmox, NAS, router. Plus a PoE switch and WiFi access point, and probably cable modem or whatever access device is there. The latter devices won’t particularly benefit from an orderly shutdown and thus don’t really need to communicate with the UPS, but the former would and do.

Probably. I haven’t played around with NUT in that way before, but compared to $300 for a network interface it’s probably worth learning.

I passed the USB connection through ESXi to TrueNAS and made TrueNAS the Master NUT. It will send a signal out to other ‘slave’ devices on the network and tell them to shutdown. In my setup TrueNAS will tell ESXi to shutdown 120 seconds after getting the signal. 2 minutes should be lots of time for TrueNAS VM to shutdown and the ESXi to shutdown. I would assume Proxmox would have similar capabilities. Maybe Proxmox can detect the UPS is on BATT and then command TrueNAS to shutdown, then shut itself down.

Yes, the PoE and Access Point likely do not even support shutdown commands. But it would be nice to have them plugged into a surge protector, even if that is the UPS.

It can be a pain in the rear getting it to work that first time but once you have it figured out, then you will have saved yourself a lot of money,. I’m certain those NIC devices are expensive because the typical purchaser is a corporation with deeper pockets that us common folk.

I did a quick search, I have no idea if this would work for you but do a search for NETRS2321E
Ebay has some for under $50 USD. Again, I have no idea if this would fit the requirement but if they did, they would be portable between any serial device/UPS.

I am curious what you will end up doing.

1 Like

USB pass-through, certainly. But neither my router nor my NAS is going to be a VM; each will be a separate system. And as my router’s going to have the lowest power consumption (it’s a fanless Qotom unit), it probably makes the most sense to USB the UPS to that, configure it as the NUT master, and then slave both TrueNAS and Proxmox to the router. Those I’d want to power off earlier, leaving the router for last.

And then I don’t need a network card for the UPS, just a UPS with a USB port–and I already have that Cyberpower model (I think an earlier version of it), and know it works with NUT.

I suspect you’re right here, and that’s frustrating–as is much of the UPS market, really. There’s no reason we should be stuck with lead-acid batteries in 2024, nor that we should be limited to communicating with a single device at a time. See also APC’s bizarre cable pinouts. An ESP32 development board costs $5 or less in end-user quantities, and that’s more than enough computing power to monitor a UPS (and its environment if desired) and put it on a network. With a little bit of creativity, it’s probably enough to control the whole thing. There’s just no excuse for basic connectivity to cost hundreds of dollars.

OK, rant over.

Dan, my two TrueNAS boxes are set up like that on a single UPS with my Protectli router as NUT master. However, be advised that, even with a lot of trying, I never could get that to work correctly with OPNsense (TrueNAS slaves instantly shut down) and so reverted to pfSense where it had always worked perfectly “out of the box”. From reading his comments on the OPNsense forum, I gather that our friend @pmh could not get it in OPNsense either. I gave up trying with the OPNsense version current at 01/31/24.

Interesting. Perhaps that means I’d need to USB the UPS to a different system instead. It’ll take some tinkering, I’d expect. Or I guess I could just throw a Raspberry Pi at it.

I prefer Eaton

Yes, some tinkering in order, I imagine.

I was disappointed with my experience. For all the reasons oft discussed here I really wanted OPNsense to work for me. But, apart from the UPS/NUT issue above, I confess I also found OPNsense more “opaque” than pfSense and I never reached comfort with it.

I look forward to hearing where you end up with this.

…or maybe just set up a LXC on Proxmox with PeaNUT:

Pass through USB to the container and it should be do the trick. Lots of ways to skin this proverbial cat.

I tried dedicating a raspberry pi to be the Nut server since my TrueNAS was being stingy with access. I could get it to work for several months, but it never was rock solid.

After a bad shutdown (utility did some unannounced work, TrueNAS did not shutdown in consultation with the Pi NUT) I decided that the Pi’s are going to have to fend for themselves, ie a different, layered strategy. My primary concern is the NAS shutting down gracefully, if the other devices get the message, great, but not as important.

So now the NAS is in charge of the UPS/NUT to ensure it will shut down as planned. Meanwhile, I am powering the more important Pi’s via USB directly off the UPS. That should give the Pis hours of runtime since the NAS is set to shutdown after a few minutes of no power.

I have also transitioned to this approach elsewhere in the network, powering multiple components with a non-communicating DC-power UPS. This should feature very good runtimes while simplifying the cable / power supply mess. For example, I use this UPS to keep my NTP servers powered up.

1 Like

Always good to provide context for people to understand why you might prefer a specific brand over something else.

How about a an APC SMT1500RM2UC? It will still need a network card (NMC), which you can easily pick up from eBay.

That is very interesting. This made me think of my RC Airplane hobby. I could take a high capacity LiPo Battery and attach a simple smart charger to it that will power one or two USB ports (Type A and Type C). It could provide power for a long time. When the power comes back, the charger will recharge the LiPo. If I ever have this kind of need, I will have something in my back pocket to use. Thanks for the idea.

1 Like

These UPS’ is something I’ve been after for years as I never saw the point of all the conversion steps (dc-ac, ac-dc) of a typical UPS just to power dc appliances. It’s super inefficient and robs the UPS of most of its capacity due to conversion, not actual energy use.

These DC-DC UPS’ also do a great job of reducing the usual cable mess and adapter crunch while providing power. Yes, there is the possibility of losing everything at once but I simply keep the original PSUs in a sealed bag nearby.

Unlike the usual APC UPS, they also do not beep incessantly, making them compatible with use in occupied spaces, especially bedrooms. A power outage is not an emergency for us, so we don’t need beeps and boops all over the house.

Some day I will DIY a similar solution for my switches since they allow very wide input voltages. At that point I’ll also make something more permanent for the Pi’s. Between Powerstream and pico-box, one can now DIY some neat stuff pretty quickly.

Considerably more than I’d like to spend. But repowering a used one might work[1]. And I’m already familiar with the AP9630, and even have a way to automate deploying a Let’s Encrypt certificate to it.

Though it’s curious that that UPS seems to have its own network interface, distinct from the 9630. Wonder what that’s about.

  1. It’s interesting that a number of the eBay listings for these things don’t include the housing for the battery pack. I understand not including the batteries themselves–why pay to ship 25 lb. of dead batteries–but discarding the enclosure seems like an odd decision. ↩︎

Two things come to mind looking at the misaligned USB port, etc. - a desire to remove said enclosures to reduce size / improve cooling performance during operation or (perhaps more likely) shipping damage.