2 x UPS to Transfer Switch to PDU - questions

[BillP]

Hi,

So I'm just a home user but I live in Africa and have frequent power cuts, and run a couple of 24/7 computers at home. When my ancient BR1500I died I replaced it with an SUA1500I Smart-UPS. Then I got hold of a second SUA1500I and currently run different devices connected to each unit. Recently I got a good deal on a secondhand AP7721 transfer switch and AP8858EU3 metered PDU.

My plan is to connect them like this - the idea being that when the mains cuts the UPS

[BillP]

Hi Ben,

I can't say I've ever done this but having your Mains->ATS->PDU is OK as long as whatever you connect to the PDU does not overload the PDU itself, ATS, or UPS loads. Typically in a data center, where the ATS and PDU are usually used, we'd only have load directly connected to the ATS and not have a PDU also.

So if I did Mains->UPS->ATS->servers, we'd install PowerChute on the servers and then you could set them up to look at UPS Network Management Cards installed in your multiple UPS scenario and only when both UPSs have shut down or are in the process of shutting down would it tell the servers to shutdown. I think that APCUPSd may support that with the network management cards too but I don't know the details. You're right that a UPS cannot connect via a UPS or PDU in any manner, including USB. The UPS USB connection is only designed to connect to a single computer. I think you'll want to check into a UPS Network Management Card for your UPSs. AP9630 is the most basic current model we offer today and it replaced AP9617 which is discontinued if you can live without firmware updates on it and just want a basic set up to get you by.

Introducing a PDU to the ATS gives you more outlets but the PDU/ATS/UPS are not designed to all talk together as it'd normally be just a UPS and load/equipment that talk to figure out a graceful shutdown for your load (or those pieces that can gracefully shutdown).

In summary, you may be able to get this to work if you have something on your load equipment watching the UPS status directly and where it can look at both UPSs and make a determination to shutdown when both are unavailable. I know PowerChute Network Shutdown can do this usually but I am sure it will require precise timing and adjusting delays and stuff like that.

As far as SNMP monitoring, I'd look at Nagios which is open source and What's Up Gold. I think WUG is probably paid but maybe looking at Nagios will get you what you need. For very basic SNMP polling, we use GetIf and iReasoning here. Not sure if it will work for you. Another to check out we use for basic traps (alert) testing is a program called Trap Receiver.

[BillP]

Hi Angela,

Thanks for taking the time to write such a detailed reply - much appreciated.

> as long as whatever you connect to the PDU does not overload the PDU itself, ATS, or UPS loads

Good reminder, but there's no chance given the low loads I'm using.

> I think you'll want to check into a UPS Network Management Card for your UPSs

Yes perhaps that is the way forward, it would give me more options, and presumably then the APCUPSD on my Macs could talk directly to the UPSes, instead of the router/usb combination. Apart from the discontinued firmware updates, is there any substantial difference between the AP9630 and AP9617?

> I know PowerChute Network Shutdown can do this usually

I've tried to install PCNS on my Mac, but I can't even achieve a successful installation of the software - the installer command just crashes. This is with Mac OSX 10.10 or 10.11, and the latest Powerchute Network Shutdown 4.1. I have to say I really like APC hardware, but it's a real shame the Mac software support is so, so poor for APC's own software.

Thanks again for the info, I should be receiving the PDU and ATS in a week or two so am sure I'll be back to ask more questions then.

Best wishes... Ben

[BillP · Accepted solution]

Hi Ben,

You're welcome - here are some comments on your questions.

On 10/22/2015 7:36 AM, Ben said:

Yes perhaps that is the way forward, it would give me more options, and presumably then the APCUPSD on my Macs could talk directly to the UPSes, instead of the router/usb combination. Apart from the discontinued firmware updates, is there any substantial difference between the AP9630 and AP9617?

Well, for what we've discussed here in regards to required functionality and with the model of UPS you have, I don't think you'll be missing out. If you ever upgrade your UPS to something newer with an SMT/SMX/SRC/SRT prefix, AP9617 won't work. Some of the general features AP9617 does not have would be multiple user log in, HTTPS updates (TLS 1.0 , cipher suites, SSL cert sizes, etc), easier log file export/download, SMTP email authentication, embedded firewall, support for localization/language packs, better SSH support for modern clients, and IPv6. Those are what I thought of for now but if you have any "must haves" you can think of, let me know and I'll tell you if AP9617 supports it or not. 

On 10/22/2015 7:36 AM, Ben said:

I've tried to install PCNS on my Mac, but I can't even achieve a successful installation of the software - the installer command just crashes. This is with Mac OSX 10.10 or 10.11, and the latest Powerchute Network Shutdown 4.1. I have to say I really like APC hardware, but it's a real shame the Mac software support is so, so poor for APC's own software.

I'll let Bill (another =S= colleague on this site) comment on this one as PowerChute is his expertise. He could probably help if you have any details on error messages during the crash, assuming the new Mac OS X is compatible with PowerChute on the compatibility chart. apcupsd should work too I think for doing all of this using its PCNET configuration. Bill also knows a little more on apcupsd.

[BillP]

Hi,

So my units arrived and so far things seem to be working as expected in that the AP7721 switches from UPS-A to UPS-B once UPS-A is exhausted. And the AP8858EU3 seems to be doing its job too.

I can log into the AP8858EU3 fine and access the web interface, but not the AP7721. My router's device list doesn't show it connected and the APC Device IP Configuration Utility couldn't find the AP7721. On the AP7721 network interface the link light is solid orange, while the status light is slowly flashing orange. My Managed switch shows a 100Mbps link. Tried to do a reset via the reset hole/button and it completed, but the same thing. Did some reading and seems one must connect to the serial interface. Is there any other way to reset the unit to some kind of default TCP/IP settings and pick up a DHCP address without requiring a serial cable? My unit was secondhand and didn't come with that cable, and getting one where I live won't be easy.

As I say the unit seems to be working fine, it's just the network connectivity that isn't.

Thanks,

Ben

[BillP]

Hi Ben,

AP77XX series ATS units have our Network Management Card 1 (NMC1) in it and in order to get a DHCP address (by default), option 43 must be configured on your DHCP server (covered here, refer to NMC1 and DHCP -

[BillP]

Thank you Angela, that's very helpful. I did the reset by pressing it until orange/green leds flashed rapidly, then pressing again, lights wnet off and it sort of restarted.

My router is Linux-based running DNSMASQ so I believe it could run the option 43, but am having trouble with the syntax required to configure the DNSMASQ options. Read some articles here but doesn't seem to work for me:

[BillP]

Ignore last message... eventually managed to configure DNSMASQ in the router to follow DHCP option 43, was able to login and disable that requirement. So all good. Thanks again...

[BillP]

No problem. Did you eventually see there is a MAC address sticker on the bottom of the ATS near the serial number sticker?

[MarkC_apc]

Angela - I was asked about the functionality of the "USB" connection on the SUA3000RMXL3U (appears to be a RJ45).  Is it compatible with most network attached servers (only one installed) so that the battery condition is monitored and the NAS shutdown on low battery?  No other functionality is required - very simple requirement.  Does not really want network management nor PowerChute software installations? Would simply buying a standard RJ45 to USB 2.x adapter work?

[BillP]

Hello,

I think a better question is to look on the NAS side and see what protocols, etc it supports for Uninterruptable Power Supplies. Yes, I have seen NAS's work via a USB connection and also SNMP when used with a Network Management Card.

If you want to try the USB option, use the standard APC UPS cable we provide with this UPS should be adequate - AP9827 is the product SKU for the cable as it is used with Back-UPS products and some of these older SUA models that have RJ-45 USB. (For anyone wondering, no, it is not the same cable used for serial connections on newer UPS models we offer like SMT and SMX SKUs.) I can't speak for any adapters but I doubt they'd work due to the special pinout on the RJ-45 port on the UPS side.

[MarkC_apc]

Thanks Angela - do you know if for this model (SUA3000RMXL3U) that a specific driver needs to be loaded onto the NAS, or does Windows (the operating system) provide this?  If it needs to be loaded, where is it available?  It does appear that most of the APC Back-UPS's are compatible with the AP9827 cable, but don't see the SUA models listed.  This SUA does have the "RJ" (50?) style USB connection on the chassis itself.