Q: Mountain Lion disconnect from Ethernet in sleep mode

It sounds it doesn't worked for me!

My iMac was asleep since 2am, at 1.30pm I tried to access it without success... It's weird because when I woke it up when I was home, I've noticed that in mail, a mail from 1pm was visible. So it was it last wake up I guess.

I really hope Apple will solve this issue with an update.

Maybe this thread will help:

https://discussions.apple.com/message/17673568#17673568

For what it is worth (not much), both of our computers reconnect to ethernet with no problem,.

I think I spoke too soon. Mine is back to the same old problem.

This is terrible.

Let me be specific with the issue that I am trying to address. I hope I am in the right forum.

We connect to a server network that is using Windows 2008 R2 with Veritas Cluster Server and a standalone DFS namespace. It is connected by 10GigE networking.

Ever since upgrading to Mountain Lion, the network connection is lost every time the computer goes to sleep. It doesn't lose internet connection, just server network connection. If the computer is running an application that is using a file from the server (e.g., xcel, indesign, word, etc...), that application will crash and the server connection is lost. One of the big reasons for upgrading was to be able to access the DFS network vs. using something like parallels.

Sometimes it's easy to reconnect and sometimes not. Sometimes trying to reconnect may put the computer into a total tailspin and causing the user to restart.

This is very, very frustrating.

I'm having a very similar issue. I have a few smb volumes being mounted on my Mac mini that are on a Windows 2008 R2 server. I upgraded to Mountain Lion last weekend, and now whenever the Mac mini wakes up from sleep mode these volumes appear to be bad.  The volumes still appear to be mounted, but when you try and use them in finder no files or directories are visible. I have an application that attempts to read data from these volumes that basically hangs because of this. A reboot is required to re-connect to the volumes.  This problem started with Mountain Lion and did not exist in Lion, Snow Leopord, or Leopord.

That's exactly what I am experiencing. The drives appear to be connected, but are not. When you try to access them, everything goes haywire. Beach balls, apps that are connected to documents on the server crash, etc...

Maybe this thread will help:

https://discussions.apple.com/message/20001867#20001867

Tried it. No luck.

I was wondering if the beta 10.8.3 was solving this issue...

Did someone test it?

How do I get the beta?

Only developpers can get it. I wanted to know if someone in this thread has the 10.8.3 and has this issue...

I may have found a solution, well I hope it will work...

I've noticed a difference between my MacBook Pro and my iMac. My MacBook Pro doesn't have the issue of disconnections while asleep.

In system preferences - network, I've noticed that my MacBook Pro has Wi-Fi, Ethernet and FireWire. My iMac has the same, plus PAN Bluetooth which was orange.

I simply deleted the PAN Bluetooth on my iMac to match with my MacBook Pro's preferences.

So far so good, the iMac appears connected all the time even while asleep for a while. I did that before sleep yesterday, I'll live it until tonight (24 hours) and I'll check if I can wake it up.

I'll let you know.

loïcfernandezcastrillon wrote:

 

I may have found a solution, well I hope it will work...

 

I've noticed a difference between my MacBook Pro and my iMac. My MacBook Pro doesn't have the issue of disconnections while asleep.

 

In system preferences - network, I've noticed that my MacBook Pro has Wi-Fi, Ethernet and FireWire. My iMac has the same, plus PAN Bluetooth which was orange.

 

I simply deleted the PAN Bluetooth on my iMac to match with my MacBook Pro's preferences.

 

So far so good, the iMac appears connected all the time even while asleep for a while. I did that before sleep yesterday, I'll live it until tonight (24 hours) and I'll check if I can wake it up.

 

I'll let you know.

I suspect that, like many other "solutions", this one is a random conjunction of (a) your taking a certain action, and (b) the Ethernent connection loss after wake-from-sleep disappearing -- for a while.

I've tried all kinds of things others have suggested, and sometimes they have "fixed" it for a day, sometimes even for a week or more -- and yet the problem would recur. The only thing I've found that is a reliable work-around -- but not a permanent cure -- is to execute (with sudo) the Terminal command sequence:

     ifconfig en0 down

     sleep 10

     ifconfig en0 up

The thing is my iMac isn't connected to the Ethernet but WiFi. My MacBook Pro is also connected to WiFi and don't have any problem. So I don't think it's a Mountain Lion problem since my MacBook Pro works well.

Sorry,  this was a good point to try. But it did not work for me (10.8.2).

I noticed by the way all kind of mobile phone profiles which I also removed. But nevertheless it did not work.