Mac Pro Waking From Sleep Randomly?

Discussion in 'Mac Pro' started by Zobrien, Mar 26, 2017.

  1. Zobrien macrumors member


    Feb 4, 2017
    Hey guys, I am curious if anyone else has this problem. I will just be sitting down on my phone and hear my fans spin up and sure enough the light on it goes from blinking to a steady on and my mouse lights up, as if it has come out of hibernation. I then go to turn on the TV it is hooked up to and it shows as no signal. Here is a few things I know: bluetooth is off, so it is not because it is connecting to anything. The mouse has not been moved, nor a key on the keyboard pressed.
    I just would like to know if this is normal, and if not, what could be causing it.
    Thanks in advance!
  2. Sublime, Mar 26, 2017
    Last edited: Mar 26, 2017

    Sublime macrumors member

    Jun 4, 2002
    Maybe network activity, optical mouse triggers it due to the surface it is resting on, another usb device doing something, some event on a schedule, handoff/continuity?
  3. 12CoreMP macrumors member


    Dec 26, 2015
    Edinburgh, Scotland
    Yes my cMP does this for about a minute every couple of hours.
  4. casperes1996 macrumors 68040


    Jan 26, 2014
    Horsens, Denmark
    Could also be that it's backing up to Time Machine if you have that enabled.
  5. Zobrien thread starter macrumors member


    Feb 4, 2017
    I wonder if it has to do if it is updating the status of something? Maybe like connecting with internet to check notifications for apps or something possibly?
    --- Post Merged, Mar 26, 2017 ---
    Hm, you may be right on that one. Thanks for the reply man.
  6. lostless macrumors 6502

    Oct 22, 2005
    It's the wake for Ethernet option. It turns on just to announce it's still on the network.
  7. Zobrien thread starter macrumors member


    Feb 4, 2017
    Hm, thanks for the info. Glad to know it is not something I should worry about.
  8. Filin macrumors regular


    Mar 7, 2010
  9. now i see it macrumors 68040

    Jan 2, 2002
    If I turn off a light that is plugged into the same wall socket as my surge strip (that has the computer plugged into it) my mac will wake from sleep every time.
  10. Zobrien thread starter macrumors member


    Feb 4, 2017
    Nope, I am a PC gamer so naturally I prefer my wired stuff lol.
    And huh, that is weird. It must be toying with the voltage of the power strip when you take it out and your Mac senses it.
  11. seveej macrumors 6502a


    Dec 14, 2009
    Helsinki, Finland
    In some cases that is intentional, in other cases unintentional. If you want to find out more...

    Open console, dig in system.log, find an occurrence of a nightly wakeup, and zero in on the line (usually the first), which contains "Wake Reason:"

    The three/four letter code gives you some info (see list below for the possible 'Wake Reason' codes (lifted from OSXDaily))
    • OHC: stands for Open Host Controller, is usually USB or Firewire. If you see OHC1 or OHC2 it is almost certainly an external USB keyboard or mouse that has woken up the machine.
    • EHC: standing for Enhanced Host Controller, is another USB interface, but can also be wireless devices and bluetooth since they are also on the USB bus of a Mac.
    • USB: a USB device woke the machine up
    • LID0: this is literally the lid of your MacBook or MacBook Pro, when you open the lid the machine wakes up from sleep.
    • PWRB: PWRB stands for Power Button, which is the physical power button on your Mac
    • RTC: Real Time Clock Alarm, is generally from wake-on-demand services like when you schedule sleep and wake on a Mac via the Energy Saver control panel. It can also be from launchd setting, user applications, backups, and other scheduled events.
  12. whartung macrumors newbie

    Dec 29, 2014
    I have this issue as well. Never could figure out what's causing it.
  13. Yahooligan macrumors 6502a


    Aug 7, 2011
    I had this problem with my wife's cMP, it would wake up every 2 hours with a reason of "Wake reason: RTC (Alarm)" and RTC maintenance, followed by everyone's favorite service... mDNSresponder. I had/have wake-on-lan and everything else turned off/disabled that would cause this. Sometimes when it would wake up (display wouldn't wake up, only the cMP), I'd go over to see what was going on and it refused to fully come out of sleep. I could ssh in, but in order to be able to actually get the display on again I'd have to reboot.

    My fix was to just never let it sleep, it's now on 24/7.

    This thread has been going for 2.5 years, still no reliable fix...
  14. snipper macrumors regular


    Feb 9, 2004
    My Mac Pro 3,1 does this too (waking up for a minute, not even turning on the monitor, then going in sleep mode again).

    And this as well.. very strange. It's only connected to an Airport via WiFi and there is a (sleeping) MBP on that Airport as well. Bluetooth is off.

    Although the "it's waking to let the rest of the netwerk know it's still there" sounds the most plausible explanation, I have my doubts. This doesn't explain why it shortly wakes when the lights go on.

    I also noticed it often wakes for a minute when I enter the room where the Mac Pro is, without touching the lights. I assume it can sense I have my iPhone with me.. even when Bluetooth is off(!). No, I'm not superstitious, just saying. It only annoys me because my wife is often already sleeping in the adjacent room, sleeping, and I don't want it to wake her.

Share This Page

13 March 26, 2017