UPS compatibility and recommendations

I remain partial to the devices manufactured by APC. Most have USB cables and OS X has built in support for their products. Simply connect your server to the USB using the USB cable and then launch System Preferences > Energy Saver. You will get a new tab providing options for how to manage power during the loss of AC line.

As for a simple way to scale your unit, multiple the volts times the amps of each of your systems. Since UPS units are rated in volt amps (VA), this is a down and dirty way of planning your scale. For example, lets say you want to connect a switch at 1 amp, a router at 1 amp, and two Mac minis at 2 amps (Mac mini: Power consumption and thermal output (BTU) information - Apple Support) then you can do some fast mental math. 4 amps * 110volts is 440 VA. An 800 to 1200 VA UPS should be adequate to support these devices. Don't overload your UPS. Too much load means no runtime.

Hope this helps. Additional planning tools are available. Also, be aware that if you are buying larger units you may need to adjust your power outlets. For example, the 2200 VA units need a 20 amp breaker and the 3000 VA units need a 30 amp locking outlet.

Reid

Apple Consultants Network

Author - "El Capitan Server – Foundation Services"

Author - "El Capitan Server – Control & Collaboration"

Author - "El Capitan Server – Advanced Services"

:: Exclusively available in Apple's iBooks Store

Like Reid, I use APC devices for these tasks, most commonly the SMART-UPS series. These are somewhat more expensive, but provide reliable power and easily ride-over and protection. These devices increase the voltage during brown-outs, too. Battery replacement is easy on the SMART UPS 1500 (SUA 1500) series, and the other models I've worked on. OS X works with the integrated power management in these SMART-UPS devices so if you have just one computer being protected, that computer can usually shut down the rest of your hardware when the battery becomes depleted during a longer outage. There's add-on open source available, and SMART-UPS has optional network management support, if you need more computers or more flexibility.

Another vote for APC. I also live in an area notorious for brown-outs and surges and regular power outages. I've had a Smart-UPS 1500 for about 13-14 years now. The batteries last about 5 years so that will be an on-going expense but the Smart-UPS will be that last UPS you ever buy.

I also have a Back-UPS XS 1300 for my home entertainment equipment, mainly to keep the PVR powered in the event of a power outage, and I have a small Back-UPS ES 500 for my cable modem to keep the Internet up, again when the power fails.

Great thing about the APC units in addition to what has been said above is that replacement batteries are easy to find either from APC or, if you want to save a bit of money, many third-parties.

How come that in my humble opinion all UPS devices which have been working with systems before 10.10, do NOT work anymore with 10.10 and above?

Could this be a hardware and software combination problem with specific Mac's or where is the problem then for such misbehavior?

I'm searching for a 100% working solution for a Mac Mini Server 10.10 setup with additional external drives where the U.P.S. device is talking to the Mac Mini AND where it is possible to manage the U.P.S. from the Mac Mini Server as well.

As noted below by myself and MrHoffman and above by Strontium90, the APC Smart-UPS series is fully supported by Apple. If you add a network card you can manage all the functions of the UPS not only from the Mac mini but from any Mac on the local network using a web browser.

Well then, can you give me some help and directions how to solve my existing problems?

In the very end, a Mac Mini Server should be used together with a APC SMT750i.

Used devices:

APC SMT750i Firmware 9.3, USB cable connected

Mac Mini Mid 2011 with several OS Systems from 10.7.5 up to 10.11.5. Each time clean install with NO data takeover.

Mac Pro 2010 OS X 10.11.5. Clean install with NO data takeover.

Synology DS710+ DSM5.2 latest version

On the Mac side, several parameter resets after each OS X installations as well as exchange of the PM battery have been performed.

Disk Repair and Permissions Repair have been done after each installation step.

All OS X versions have been updated to the latest available public versions.

Except for the mentioned test with Apcupsd.org, which was done after all clean Mac OS X tests.

Except the Synology DS710+, which does send the required shutdown command to the APC SMT750i to switch of the output mains power (I can see the messages on the display of the APC SMT750i), all of my Mac's with all mentioned systems (each one a clean install without anything else) do NOT send this command to the APC SMT750i as it doesn't perform a shutdown and also no messages on the display of the APC SMT750i.

Even if I do all the test with the open source Apcupsd 3.14.14 software, the relevant kill/shutdown signal TO the APC SMT750i will never be sent.

On the Mac Mini only USB3.0 is existing, on the MacPro 2010, USB2.0 and USB3.0 over a USB3.0 PCI Card has been used to test.

In my humble opinion, this must be a real serious bug in all OS X Versions in conjunction with APC OR

all of my Mac's are somehow dead/defect OR

I'm just tooooo old (>53) and lousy to get this working properly.

Is there somewhere a description for guidance to figure out, why the OS X doesn't send the required shutdown command over USB to the APC BUT the Synology does?

Thank you for anyones help.

External batteries can be used to keep a macOS server box powered up when the mains are out obviously subject to the available battery capacity, or some folks can choose to use the external power supply as a power switch. Because this is looking rather more like the latter case, and the rest of this thread is about the former and the USB commands sent from the power supply to the macOS system that tell macOS it's time to shut down.

AFAIK, macOS doesn't have integrated mechanisms to send a shut-off command to an external power supply device, so — if the add-on apcupsd software isn't working to your needs here — then you're headed toward sending a feature request to Apple, and/or a bug report to the folks maintaining the apcupsd package, and/or add or replace some of the external hardware and integrate a network-controlled power switch into the configuration.

I'd be somewhat surprised to see the standard macOS environment even send a hard power off command out too, as that might well leave macOS in an odd state, possibly with data corruptions.

AFAIK, macOS doesn't do what you seem want here. It certainly doesn't provide much (if any) control over the status of an external power supply.

Thank you for feedback.

According to the man page for "shutdown" and the Apple own bash script "/usr/libexec/upsshutdown", exactly this procedure I'm talking about should be the way Apple does handle UPS situations of power loss.

Or I'm totally wrong and misinterpreting things?

From the man page of "shutdown":

-u The system is halted up until the point of removing system power,

but waits before removing power for 5 minutes so that an external

UPS (uninterruptible power supply) can forcibly remove power.

This simulates a dirty shutdown to permit a later automatic power

on. OS X uses this mode automatically with supported UPSs in

emergency shutdowns.

And the content of the bash script upsshutdown:

#!/bin/sh

#

# Initialize...

#

PATH=/bin:/usr/bin:/sbin:/usr/sbin

SI_PATH=/System/Library/StartupItems

MSG="Shutting down due to power loss!"

logger -i -p daemon.emerg -t UPS "${MSG}"

#

# Take the system down.

#

if [[ -n $1 && "WaitForUPS" == $1 ]] ; then

#

# Wait for UPS to take the system down abruptly and unexpectedly.

#

shutdown -hu now "${MSG}"

else

#

# Gently shutdown the system immediately.

#

shutdown -h now "${MSG}"

fi

----

You're mis-understanding the relationship between the Mac and the UPS. The Mac does not send shutdown commands to the UPS the Mac shuts down based on UPS power state.

The UPS sends its power state to the Mac and the Mac will shutdown at the appropriate time based on default settings or based on what you have set in the Energy Saver preferences.

That shutdown script is how macOS gracefully shuts itself down when the resources of the external power supply are determined to be exhausted.

macOS does not tell the external power supply to shut down the power. Not without add-on software.

That five minute wait — not sure whether (if?) that's what is confusing you here — is how macOS enables itself to automatically reboot when power is restored. (macOS does different things on power up, largely dependent on what happened right before macOS shut down or crashed or had its power plug pulled, too.)

If you want to manage the external power supply — to treat the external supply like a switch — then you're going to need additional software and an external power supply that itself supports remote management.

From the APC SMT750 specs: "The UPS SmartSlot lets you use a network management card to remotely manage and control the UPS." It's that add-on remote management card that provides full remote management and monitoring. (How similar that SMT750 model is to the SMT750i that you're using, I don't know.) If your unit has that network card, then get that configured and working and then have a chat with the folks maintaining apcupsd if that configuration doesn't work or doesn't meet your needs. (But I'd still be cautious about sending a shutdown request to the power supply, as I'd rather not have the power yanked underneath macOS — avoiding that's why folks are using an external battery power supply, after all.)