No Wake-on-LAN possible since updating to ML

@Chasb441

So both of us are still waiting for a solution from Apple. I hope you did'nt mind my reply, I usually add a ;) to tell, that is more fun than seriously being upset. So accept my apologize aswell.

Best regards from Madrid.

I have a variety of different Macs in my home, and some testing showed that the issue varies by the Mac model. My biggest concern was waking my 2009 Mac Pro via LAN. What I found was that when jumbo frames was enabled (MTU=9000), the Mac Pro failed to respond to the Wake On LAN command. When I set the frame size back to standard (MTU=1500), it now responds to Wake On LAN.

Newer Macs in my home don't seem to have this same issue. So I'd say to give this a try.

To be clear I confess, that I havn't read the entire thread, but for me the WOL works within the LAN (Mac Pro, early 2008), if I set the subnet mask in the "Wake on LAN" app to 255.255.255.0.

By this, the magic packet is broadcasted to all devices in the LAN.

What is more cumbersome for me is to Wake the Mac over the Internet. This is, because my router (Netgear Wndrmac) doesn't support to forward the incoming magic packet to a broadcast address and it isn't also not possible to set a static entry in the ARP table (the problem seems to be here, that the ARP table of the router isn't updated anymore, when the mac goes to sleep, so it is no more possible to route the magic packet directly (by IP address) to the sleeping mac.

I'm actually looking for a workaround for this by adding a (real) hub between the router and the mac with a device being up attached to the same router (to have an IP address to send the magic packet - a classic hub broadcasts the packet then to all its ports...)

Hello everyone, finally, I say finally because I've tried and tried many many stuff to fix this **** boring issue. And after many tests on different iMacs, I finally have one solution that should work for all of you.

I'll tell you what I did on my iMac and on my friend's iMac, and now they both wake up when we use a remote app like team viewer/screens... I made some tests, even after 12 or 24 hours of sleep, the iMac still wakes up when I use my VNC app from my iPhone or "Back to my Mac" from my MacBook Pro.

If you want to try :

1. Repair disc permissions, to make sure everything's fine on your Mac. If you see that some permissions have been repaired, launch another repair until the list of permissions is empty.

2. Open terminal paste that and hit enter: sudo periodic daily weekly monthly,

It will ask for your password, type it. Then paste and hit enter: sudo dscacheutil -flushcache.

3. Turn off your Mac.

4. Start your Mac while holding the left shift key until you see a progress bar, let the Mac start, wait for 3 or 5 min. Then turn it off.

5. When your start it, reset the PRAM.

6. You're good!

I made that on both iMacs and now they work like a charm. I guess the 2 commands in terminal solved the issue, because I made the other steps for weeks without success before.

Hope it will work for you.

Hi,

Did try your workaround on my Mac Mini Late 2009 (like all the workarounds mentioned in this thread).

Unfortunatly no luck for me.

Anyone else luckier than me?

It is still working fine for me, the only moments I wasn't able to reach the iMac when I wasn't home were because my router change its IP sometimes, so I've installed the "Screens" app on my iMac that retrieves the IP, sometimes it can take 15min, so it was the only moments I wasn't able to access it.

Otherwise, when I'm home on WiFi, no trouble at all!

I'm just guessing here, but maybe its a firmware problem.

The darkwake feature isn't working either... and thats definitely firmware related.

Don't think there will ever be a solution for older macs.

How old are the iMacs you tried it on?

iMac early 2011, I also have a MacBook Pro late 2010, and this one doesn't have any trouble, so it's not Lion or Mountain Lion's fault, but a firmware update as you said.

I remember, when I had my iMac the first days, it was working fine with Wake on Lan, except sometimes while using it, it was loosing the WiFi connection. A few days after that Apple came with an update to solve this WiFi issue, since that moment the problem came.

I'm happy to have solved it, I hope it will work, cause sometimes it works for a few days and then the problem comes back... So I cross my fingers 🙂

WOW I forgot to mention in my previous posts, that just after turning the iMac off, I unplugged it for 10min or so in order to reset the SMC.

Do you use an AirPort base station such as Time Capsule, AirPort Extreme or AirPort Express?

I've checked Computer/Library/Preferences/SystemConfiguration

There is a file called "preferences.plist"

Into it I found:

</dict>

<key>PPP</key>

<dict>

<key>ACSPEnabled</key>

<integer>0</integer>

<key>CommDisplayTerminalWindow</key>

<integer>0</integer>

<key>CommRedialCount</key>

<integer>1</integer>

<key>CommRedialEnabled</key>

<integer>1</integer>

<key>CommRedialInterval</key>

<integer>5</integer>

<key>CommUseTerminalScript</key>

<integer>0</integer>

<key>DialOnDemand</key>

<integer>0</integer>

<key>DisconnectOnFastUserSwitch</key>

<integer>1</integer>

<key>DisconnectOnIdle</key>

<integer>1</integer>

<key>DisconnectOnIdleTimer</key>

<integer>600</integer>

<key>DisconnectOnLogout</key>

<integer>1</integer>

<key>DisconnectOnSleep</key>

<integer>1</integer>

<key>IPCPCompressionVJ</key>

<integer>1</integer>

<key>IdleReminder</key>

<integer>0</integer>

<key>IdleReminderTimer</key>

<integer>1800</integer>

<key>LCPEchoEnabled</key>

<integer>0</integer>

<key>LCPEchoFailure</key>

<integer>4</integer>

<key>LCPEchoInterval</key>

<integer>10</integer>

<key>Logfile</key>

<string>/var/log/ppp.log</string>

<key>VerboseLogging</key>

<integer>0</integer>

Do you think we could solve the problem by changing some of the values?

loïcfernandezcastrillon, you magnificent *******! That toally did the trick for me.

If the part where you start up in safe mode is necessary, I'm wondering if it's clearing and rebuilding the kernel extension cache that's key.

Thanks a lot, what did you try? Changing the values of prefrecences.plist, or what I said before?

Because the problem goes away for a moment, and comes back for any reason...

Whoops. Celebrated prematurely. It came back. Though, this time, the other computers on the network thought it as still wakeable. So I guess that's a start?

I've got one computer running Mountain Lion that has wake for network access working perfectly, and one that doesn't. When I have a minute, I'll compare the plists in the SystemConfiguration and see if there are some relevent-seeming differences between the two.

I do have the same issue, my iMac looses connection during 6-8 hours of sleep, my MacBook Pro does not.