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System keeps waking from sleep every 2 hours

Since Yosemite update, system keeps waking from sleep approx. every 2 hours. It goes back to sleep on its own but keeps waking up again. I have "wake for network access" in System Preferences turned off. Here are samples of the console messages:


10/19/14 1:02:43.000 AM kernel[0]: Wake reason: RTC (Alarm)

10/19/14 1:02:43.000 AM kernel[0]: RTC: Maintenance 2014/10/19 08:02:43, sleep 2014/10/19 06:14:45

10/19/14 3:00:41.000 AM kernel[0]: Wake reason: RTC (Alarm)

10/19/14 3:00:41.000 AM kernel[0]: RTC: Maintenance 2014/10/19 10:00:41, sleep 2014/10/19 08:12:51


I have no idea what "Wake reason: RTC (Alarm)" means. Any help would be appreciated.

iMac, OS X Yosemite (10.10), 2011 iMac Intel Core i5 12GB RAM

Posted on Oct 19, 2014 5:20 PM

Reply
109 replies

Jan 10, 2017 9:25 PM in response to James Brust

Same issue but in El Capitan. Looked this up, and RTC alarm is a common feature on PCs (https://en.wikipedia.org/wiki/Real-time_clock_alarm). I have cron and other background tasks that run periodically, so my guess is it's one of those. But I don't have time to hunt it down for now, so I'll disable wake-on-LAN and "start after power failure," and if that doesn't work, I'll just disable sleep and let it run.

Feb 23, 2017 12:06 PM in response to GaryKing

This seems to work on my Yosemite system:


sudo defaults write /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist ProgramArguments -array-add -DisableSleepProxyClient


Basically, this adds a <string>-DisableSleepProxyClient</string> as the last entry in the ProgramArguments.

You then Restart to make it take effect. This may affect the "Bonjour Sleep Proxy". I haven't tested it. What I do know is that my RTC (Alarm) has stopped.

Feb 23, 2017 2:40 PM in response to dickguertin

Well, I can't seem to be able to Edit my previous post. The change I suggested works TOO WELL. It causes things like remote login to that computer to fail (timeout). It also affects BonJour Remote Printing. I had to undo the change to the plist. manually removing the <string>-DisableSleepProxyClient</string>. Sorry about this. If I could retract the post, I would.

Oct 20, 2014 6:24 PM in response to GaryKing

Same/similar issue.


Oct 20 16:29:39 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 20 16:29:39 kernel[0] <Notice>: AppleCamIn::systemWakeCall - messageType = 0xE0000340

Oct 20 16:29:39 kernel[0] <Notice>: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us

Oct 20 16:29:43 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 4358 milliseconds

Oct 20 16:29:44 kernel[0] <Notice>: AppleCamIn::handleWakeEvent_gated

Oct 20 16:30:04 kernel[0] <Notice>: ARPT: 3331.330078: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake

Oct 20 16:30:04 kernel[0] <Notice>: AppleCamIn::systemWakeCall - messageType = 0xE0000340

Oct 20 16:30:08 kernel[0] <Notice>: AppleCamIn::handleWakeEvent_gated

Oct 20 16:30:51 kernel[0] <Notice>: AppleCamIn::systemWakeCall - messageType = 0xE0000340

Oct 20 16:30:51 kernel[0] <Notice>: AppleBCM5701Ethernet [en3]: 0 0 memWrInd fBJP_Wakeup_Timer

Oct 20 16:30:53 kernel[0] <Notice>: AppleCamIn::systemWakeCall - messageType = 0xE0000340


User uploaded file

Oct 22, 2014 9:34 AM in response to James Brust

Yes I get the same thing on my 2008 mac pro. It wakes from sleep about every 2 hours. It does some thinking, then goes back to sleep. Probably not a issue with a macbook or imac. But these older mac pro's make a **** of a racket firing up all 5+ fans at 3am:(


I did a fresh install on a new hdd. No other software installed. All sharing options, including wake for ethernet is turned off.

I'll bee booting of the mavericks drive for a few more months until Apple solves this.


Googling this issue, gets plenty of results. It's pretty widespread. I'm surprised Apple did not catch this one during testing.

Oct 22, 2014 11:04 AM in response to mediahound

Power Nap is not the problem anyway. I have it off on my Mini, as do a lot of other people. It's almost definitely a bug, based on the multiple threads about it. It's specific to Yosemite. I'm just hoping it gets fixed soon.


There are some quick fixes for it that require changes in the Terminal, or plist files, but I'm weary of doing those. I'm willing to wait for an official fix; hopefully one arrives within a week or two.

Oct 22, 2014 11:18 AM in response to GaryKing

Same here on an 2009 Mac Pro even with everything switched off in energy saver and no applications running.


Others have even tried clean installs to solve it but it persists so it seems to be an OS X bug unless this is now considered normal behaviour.


It is related to the new discoveryd process as it is possible to stop it by editing a plist (see here http://ispire.me/fix-yosemite-rtc-alarm-wakeup-issue/) however this causes other problems so we have to hope an official fix comes soon....

Oct 22, 2014 11:48 AM in response to James Brust

As GaryKing said, there are some stated fixes out there that require Terminal commands.I found this one on several sites and copied (I now can't find the original sites to give a link unfortunately). A number of people said it worked perfectly. But I haven't done it because I too am leery of using commands where I don't understand exactly what they are doing. If anyone wants to try this & report back that would be great. Here's the supposed fix which disables discoveryd and enables mDNSResponder (I don't pretend to understand those are!)



Disable discoveryd:


sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.discoveryd.plist


Enable mDNSResponder:


sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist

System keeps waking from sleep every 2 hours

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