No Wake-on-LAN possible since updating to ML

Yea you are correct. I thought it helped at first, but it ended up not being a solution. I agree with Randall Jenkins, if you are able, everyone should submit a bug report.

I also suspect it has something to do with the new Power Nap feature. They must have rewritten the "wake on" feature in OSX

i'm running a wired LAN connection for my iMac and had similar issues to everyone on this thread (although i did experience this on Wi-Fi as well). After reviewing a number of different threads over different OS versions, I tried the following and it has given me success today, although preliminary it is much better than I have been at any point in the past.

In the network settings, people had mentioned re-arranging the network connections in order (ie. put Ethernet or Wi-Fi on top) . That suggestion did not work for me. What I did change here was the locations. Typically you would see Automatic and maybe Home. I added a brand new one and switched to that location. I then deleted the previous locations, so just the new one remained. When I activated, my connection was dropped and it re-established getting a new IP address, etc from DHCP.

What makes me interested here is that when the new profile was created instead of using an old one, it added a new type of network adapter that was Bluetooth related in addtion to the existing ones.

Since that change, the iMac finally allowed network traffic when asleep (remote MacPro, Apple TV etc..) I reduced my sleep time to 15 minutes and have tried a few times today and it has been waking up consistently on LAN traffic. I've tested by putting to sleep via VNC, seeing the iTunes connection disconnect and then reestablish when I selected it again. I will let this run for a while and see. Hope this helps someone out. At best a workaround, but I'll take it considering the frustration I've had with this for a while.

Thanks for the info, I have tried this and managed to get an iMac to wake on several occasions over a 16 hour period from both a MacBook Pro and iPad and thought I had cracked it. Alas shortly after I thought this had worked it vanished from the network again. If you can let us know how you get on testing your setup that would be helpful. I will test it again as I may have missed something and post back the result.

Thanks from me, too. Unfortunately this hint didn't work better. I put all my hopes on the next ML bugfix, hoping it comes earlier than we all expect it 😉.

nice weekend to all of you....

unfortunately mine has dropped again and won't wake up.. After my previous test, i deleted everything but the ethernet connection. i think what actually made it work was the fact that I didn't realize that Wi-Fi was somehow simulataneously enabled at the same time as my Ethernet connection. I think the wake-up is happening through the wi-fi side.. with it reenabled it is waking up again. Definitely bugs on pure Ethernet side on this.

Just to add to the numbers here. I upgraded from Lion (which had been a clean install on a brand new HD installed by an Apple authorized service center on my 2008 iMac) to ML 48 hours ago. Now it appears that "Wake for Network Access" isn't working. That setting was in place before the upgrade and afterwards, has never been unchecked.

In my case, I don' t have anything fancy, just my iMac and my home wifi network via a 2011 Airport Extreme base station. Until ML, when I woke up my iMac in the morning, if I'd left my browser open, I'd find all my new emails in the Gmail inbox, all the overnight notices loaded in Facebook, etc. And if I'd left a download or upload going the night before, it would be completed.

Not so under ML. By the way, the wi-fi network keeps working just fine when the iMac is asleep - I've confirmed that via other devices including my Kindle Fire tablet and my Rokus. No problem connecting them to the internet by wi-fi.

But the iMac sleeps regardless if an upload or download is happening, and has no internet connectivity until I wake it up again.

I've specifically been using Safari so as not to confuse the issue with "3rd party apps." I've been uploading some photo files to a secured area my online photo site, which I do occasionally as backup. That's 4 or 5 GB at a session, and it makes sense to let that run while my iMac and wi-fi network are otherwise idle. But after repeated attempts and experiments, it's clear that when the iMac is scheduled to sleep, it just does, and stops its internet connectivity. I've come back at least twice after 2 hours, and also once after 8+ hours, to find the upload had stopped when the iMac went to sleep.

I've set the preferences to have the "computer sleep" at 1 hour, and as noted the "wake for internet access" preference has always been checked.

I have performed SMC and PRAM resets. This has not solved the problem. I will file a bug report (thanks to those who posted the link).

I really don't want to set the "computer sleep" to "never," since my iMac does get really warm when running and I worry about the wear and tear of all that heat on the hardware.

I'm not a techie, just a fairly expert computer user. I've had a Mac for 4 years and have enjoyed its reliablity. I hope this isn't a portent that I'm in for a PC-like future with my Mac: having to start tinkering under the hood just to do very simple home-user things with it.

Message was edited by: Suzatlarge

Hi!

Just want to add up to the numbers here that I still have the problem with no WOL on my Macmini (late 2011), iMac (2011) and MBPr. I filed a defect report to Apple two weeks ago and have to this moment not received any response. I sincerely hope that there is some activity to solve this issue in Cupertino since this issue in no way could be considered as a minor flaw especially for those Macmini owners out there that uses this thing as a server.

I have tried out the workarounds posted in this forum with no luck but I'm thankful for the efforts provided by the community.

Wake for network access still not working with 10.8.1 on my Mid-2011 iMac 27" i7. Irritating to say the least.

Agree, 10.8.1 didn't fix any problems concerning wake on lan and/or stability of lan/wlan connection between macs running Mountain Lion.

I didn't get any response from Apple yet, related to my bug report. I'm not happy with the situation.

Same thing here. WOL not working w/ 10.8.1. Bug report submitted.

I found a fix. It requires editing system prefs plist to disable dark wake. Reverse these instructions to restore dark wake. Use at your own risk, I am not an expert.

This allows your ethernet connected mac to wake on lan using a magic packet (with "wake for network access" checked in Energy Saver preferences).

Open /Library/Preferences/SystemConfiguration/com.apple.Boot.plist using a text editor

Change this:

<key>Kernel Flags</key>

<string></string></dict>

</plist>

To this:

<key>Kernel Flags</key>

<string>darkwake=0</string></dict>

</plist>

Save the file, reboot, and you are in business.

Thanks D. Rue, this worked perfectly for me so far.

Hey Kevin,

The waking has been working for me too. Have you noticed any thing different with regards to how your Mac goes to sleep now? Mine doesn't seem to sleep on it's own - I have to ask it to.

Hi D.Rue,

this work better than other workarounds, but there are still problems remaining with already connected shares and with network traffic during the Mach goes to sleep. Examples:

a) a share is connected via alias, the server went to sleep. Using the share makes the mac freezing.

b) a large download is in progress, the Mac ignores the traffic and goes to sleep.

that didn't happen with 10.7.

A proper final solution should keep all Macs alive, as long there is any acess or traffic regarding the Macs.