Internet connection lost after sleep - Ethernet

On august 8 I wrote on this forum what has been helpfull for me. Since April the problem has never occured anymore. Without any problem a few months ago I even changed my Sitecomrouter for an Apple timemachine.

Really, never happened again. Before almost every day.

I started to see this exact problem with Lion when it was released. Using an Airport Extreme since the the 1GB Ethernet (pre-Time Capsule) model. No network changes in years. Wired Ethernet to this computer.

Never had this with a G5 PowerMac, Mac Mini (SL or L), but my iMac 27" with Lion had it bad.

Then it went away and now only happens sporadically. Even when it happens now, it self clears. One of the Lion updates made it better. Still, very irritating when it does happen. Happened just yesterday. They don't have right, just better.

I have iMac 27" 2010 late 2010 model. My Ethernet does not work up after I installed Lion. It was working for few days and then it disappeared from my system preferences.

I have tried to restart several times my computer, but its not chanage. My repair warranty just expired last month and I don't know what to do. Anyone has any idea on how to fix this. If it was working for 1 year on Snow Leopard. It has to do soemthing with drivers.

The first thing to do is to diagnose the problem.

From the Apple Menu, select "About This Mac"

Click on "More Info..."

From the "System Information" window, select "System Report..."

Under Hardware, see "Ethernet Cards"

It shows you your Ethernet card information.

First, make sure the above shows up for your Ethernet interface

Somewhere there is a diagnostics report in the program too.

Chances are your problem can be fixed with software.

Well this is what I get when I go to my System Info.

I hate to say this, but this does not look good.

It should show the Ethernet controller data.

It still could be software, a corrupted configuration file or driver file.

I would shutdown and restart the computer, which you have probably done just to see if this magically fixes everything.

At this point, you have enterd territory I have never had to deal with. You could also make an appointment at an Apple Store with a "Genius" to help.

You should research how to use the Lion Recovery partition. I placed a link below to a descriptive page. If you restart the computer and hold down the Option key as soon as the startup chime goes off, you should end up with a choice of your main disk and the Lion Recovery Partition. Boot from Recovery and see the article below. It has an even better and more direct way of getting into recovery mode.

Read this (I found it searching Lion Recovery)..

http://support.apple.com/kb/HT4718

It tells you just what you can do with the Lion Recovery Partition. Bad news after reading it. If your Ethernet interface is really broken, it may not help you at all. But if WiFi still works, you are good and can use it.

I hope this does help!

Good luck.

I tried every thing suggested so far to no avail. So I used Energy Saver Prefs to never sleep and the problem was avoided unsatisfactorily.

Two days ago I applied the brand new Time Capsule firmware update (via Airport Utility) and turned sleep back on — working a-okay ever since!

oh man.....this worked for me! thanks

gnlpf wrote:

I’ve done some testing and it least in my case it seems to be a problem with Apples mDNSdaemon.

The problem seems to affect only programs like Safari or Mail. If these programs are losingtheir internet connection, eth0 is still connected to my local switch. Pinging resources in my local LAN or the internet (like google. com) is still possible. I checked the system log and stumbled across entries like this:

mDNSResponder:ERROR: mDNSPlatformReadTCP - recv 37 got CLOSED 117000 times

Afterstopping/restarting mDNSResponder with the following command:

sudo launchctl unload /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist

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

Safari andMail had immediate internet access again. So from my point of view, there must be something wrong with Apples special DNS daemon mDNS.

I’ll have a chat with a Apple tech tonight, will be interesting to see what they are thinking.

I have found the exact same issue on my machine (early 2011 15" MBP). This began after installing the most recent SMC and EFI updates (and iTunes 10.5.1 and Java for 10.7 Update 1, FWIW).

Also after these updates I've experienced multiple occasions where the machine just locks up and no longer accepts mouse/keyboard input. Every minute or so it'll burst with some input (e.g. move the cursor some) but it goes back to being frozen. I tried closing the lid to trigger sleep but the machine stayed on and the screen fully on. I had to do a force poweroff in each case to get back to work.

I'm suspecting the iTunes update for the mDNS issue and the EFI/SMC updates for the lockup issues.

I called yesterday to Apple Customer Suport. I was told to do fallwoing things:

Restart Computer

Restart Computer Again

Press Key: Control-Command-R -P and keep till computer beeps 2 times, then release.

I was told it reset default firmware setings of my iMac.

My etherned card now works as I would expect. It shows-up in lion osx System Preferences > Network.

I did write that a page or so back...

Works for me.

I only read the first couple and last page of comments here, so forgive if this shows up elsewhere, but from searching lots of other places, this seems to have fixed the issue for some folks. I'm about to try it but since it requires restart, thought I would offer it up here before my Safari session is gone.

1. Delete your network from the list of preferred ones in (Apple) >System Preferences > Network.
2. Open Keychain Access and delete any items in Login and System for that network.
3. Repair permissions using Disk Utility. (Some people had success without this step, but it's not bad practice to be on the safe side).
4. Reboot, find your network and enter your password to rejoin it.

One other solution someone proposed:

1. (Apple) >System Preferences > Network, under Wi-Fi, click on Advanced button, go to the DNS tab, and add the Google public DNS: 8.8.8.8.
2. Click OK, then Apply
3. Turn your wifi off and back on again.

Again, haven't tried either of these, and I think I'll try the first one to see if it solves the issue before trying the DNS change. I'll make a point of coming back to comment if neither works.

the Time Capsule firmware update fixed the issue for me as well

Thanks to all

I thought the this issue was resolved for me but it has reared its ugly head again after ~3 weeks. I have tried everything everyone has posted prior to Dec 1, 2011. I will try everything posted after that date. I keep seeing that people are talking about the Time Capsule Firmware update. I don't run anything on my computer that would require a time capsule update. So, I don't think the Time Capsule firmware update is the solution. The PRAM reset has been doing the job though it is short lived.

I'm just here to chime in that I am and have been having this same problem ever since owning my 2011 iMac 21.5 base model.

Periodically, when waking from sleep, it'll take anywhere from 30-60 seconds for restablish connection via ethernet cable. What helps, strangely, is turning WiFi on/off, if I don't want to wait the 30-60 seconds. I'm not sure why this is, but this somehow gets the ethernet connection back.

I've tested the router, the cable connection, upgraded firmware, and concluded that it isn't hardware related (connecting the ethernet cable directly from modem to iMac--meaning without the router--allows for perfect establishing connection upon wake). Like others' experiences, my router gives connection to my phone, my PS3, and my laptop perfectly fine.

I've tried some of the "solutions" on this thread, and to no avail. I think this is something to do with Lion. Just throwing in my two cents, and hoping Apple addresses this in a future update. It's very frustrating and disillusioning my Mac experience.