MY computer awoke from sleep mode in the middle of the night. Is it possible that my IP address was being pinged from a non creditable source?
iMac, Mac OS X (10.7.5)
See this discussion
Lately my Mac won't stay asleep. Wakes up on its own.
and some options by Eric Root and link to
There should be a noted event in the Console logs from the time it occurred.
The actual restart is a curious happening, from a sleep state to some event
that was seen as a need to restart, may invite a look into a kernel panic or
other issue. If your Firewall in the system (the OS X firewall in security) is set
to not allow any uninitiated contact with your computer, it shouldn't see an
outside source as a reason to wake up and restart.
There are times where some of my computers wake up (since they are left
to sleep) due to some localized occurrence such as a interference from an
item using the same wireless band the wi-fi occupies; or since mine are
protected from power fluctuation by UPS, it may sense a change of voltage
and engage the battery; thus it would wake up... Or if I come into a room in
with certain outer jacket of fabric known to make static, the static discharge
will wake the computer(s) in the room. Not all. But not restart any.
And then there's this:
•About Wake on Demand and Bonjour Sleep Proxy - Apple Support
So the Console logs and other settings in your system should be checked.
However, the finding of information there does not help me; perhaps some
one who is able to read the Console and command-line logs will assist you.
Once in a blue moon, a kitty will become keyboard-inspired, to restart a Mac.
Good luck & happy computing! 🙂
Check to see if the 'Start up automatically after a power failure' checkbox the bottom of the Energy Saver screen is checkmarked.
, System Preferences, Hardware, Energy Saver as shown below.
A momentary power outage could have caused the computer to restart.
Mid-2011 iMac 12,1 21.5 screen with OS X 10.8.5 "Mountain Lion" installed. Your system and System Preferences screen might not have this option.
Thank you I looked and the check box is not checked for "start up after a power failure". There certainly was no power outage when it occurred. Despite not having selected this option, I am assuming a power spike may do the same thing? The other piece to this was my wife's iPhone awoke mysteriously as well!!!! There were no notifications, email, texts, etc…….This was followed by our HP office jet printer also resetting itself from sleep mode. any other thoughts??
In my own experience, it is usually low line power conditions ("brownouts") that cause electronic devices to freeze or reboot.
Surges (sudden increases in line voltage) certainly can do damage (especially when a lightning strike enters the power line), but seldom cause a reboot.
If these events occurs frequently, you might consider an inexpensive plug-in device that quickly show power outlets are properly wired and grounded. If wiring problems are found, of course, obtain the services of an electrician.
A quality uninterruptable power supply can provide a few minutes of battery backup should the line power go down, and can also provide effective filtering of a 'dirty' power source. One company I've used for such devices in the past is American Power Conversion: http://www.apc.com/template/country_selection.cfm
My computer mysteriously awoke from sleep mode in the middle of the night accompanied by the restart/power up sound. How is that possible?
