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UPS Energy Saver on MacBook Pro for External Drives

995 Views 7 Replies Latest reply: Oct 1, 2013 5:53 PM by markntosh RSS
markntosh Calculating status...
Currently Being Moderated
Jan 26, 2012 10:29 AM

A search here has shown this topic come up before -- such as at and -- but I can't find a resolution, so I'm bringing it up again.


I have multiple FW drives connected to my MacBook Pro. The MBP is connected to an APC Back-UPS RS 1200. OSX does not make the UPS Energy Saver autoshutdown preferences available on the MBP, the reasoning being that a laptop shouldn't need UPS autoshutdown because it has its own battery which is likely to run for far longer than the UPS would.


That's all well and good for the MBP itself, but it doesn't account for the multiple FW drives which are attached to it for backups and other purposes. In the event of a power outage, without UPS autoshutdown, the UPS will run down, and the drives will abruptly power off, exposing them to potential data loss and damage.


It's also not a solution to suggest that I manually power things down once there's a power outage, because the power can go out while I'm away for more than the few minutes of UPS battery back up time. The only real solution is to have UPS autoshutdown available on all portable machines. Unless and until Apple offers a (surely very simple) OS update to make that happen, I'm still interested in a solution.


APC's own software for autoshutdown stopped being updated long ago, so there is no version compatible with Snow Leopard.


The only potential solution I've found so far is -- but its documentation is overwhelming and it appears that it may need other supporting software, a fair amount of Terminal usage, etc., all making it not very user-friendly for the very simple usage I'd want to make of it.


Does anyone know of any other solutions, software that can run on a MBP to add UPS autoshutdown functionality?


Re: Apcups, is anyone using it successfully on a MBP? If so, does anyone know if the version listed here -- -- is a simple application that I can easily install and configure like regular Mac apps? If yes, then I'll likely be very happy with no need for the following question. If no, can anyone provide simple instructions to set up Apcupsd to do what I want?

MacBook Pro (17-inch), Mac OS X (10.6.8)
  • Kappy Level 10 Level 10 (221,035 points)
    Currently Being Moderated
    Jan 26, 2012 10:38 AM (in response to markntosh)

    If I remember correctly if the computer is running on battery power then all the external ports are turned off - USB and Firewire. So that would seem to preclude a need for an external UPS.


    As for the autoshutdown concern you could write an AppleScript to handle that or use a third-party utility that will perform a shutdown when an event occurs.

  • Shootist007 Level 6 Level 6 (16,640 points)
    Currently Being Moderated
    Jan 26, 2012 11:12 AM (in response to markntosh)

    If for some reason the normal power goes out and you are not anywhere near the computer it really doesn't matter if the external drives use up the UPS power and shut down. You are not doing anything on the computer so no files should be writing to the drives.

    If you are using the computer when the power goes out just eject the drives and turn them off before the UPS power runs down.

  • eww Level 9 Level 9 (52,975 points)

    "You are not doing anything on the computer so no files should be writing to the drives."


    Big assumption there. With today's notebooks so capable of acting as desktop substitutes, they are often left running unattended to complete demanding tasks overnight or while the user does other things.


    To be able to suspend such activities and gracefully power down an external drive or drives in the event of a power outage, the Mac would have to have instructions from each third-party application or process that is running about how to interrupt its activity safely and without jeopardizing the integrity of whatever hard disk directories are in use. Then it would need to unmount the drive(s) and, if they were bus-powered drives, turn off the power to each of them at the port to which it was connected. I bet it would be possible for all app developers to write such instructions into their apps' code, but where's the incentive for them to do so? This isn't a feature that most users would gladly pay extra for, I suspect, and the cost of adding it to apps that don't have it now and testing it for reliability and proper function under all conceivable circumstances would not be trivial.


    If the drive(s) were AC-powered, the computer wouldn't be able to power them down itself -- the UPS would have to do that, or simply leave them on and power them until its battery was depleted or the AC was restored. It wouldn't matter which happened as far as the drives and their contents were concerned, because once the computer stopped using them, powering them off would be safe at any time.

  • Arpamac Level 1 Level 1 (0 points)

    Jettison is a utility that unmounts drives before the laptop sleeps. As of this writing, it's $1.99 from the Mac App Store. I have no connection whatsoever with the developer/seller.


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