Internet connection lost after sleep - Ethernet

Has anyone thought how advantageous this 'fault' would be to those with evil intent, who would like your computer left active and available to be used for denial of service operations?

Why does it affect perhaps only one of identical machines, is it because one has been compromised? It seems that not many mac users employ antivirus software.

However I had this problem on a pc running Vista, that started when I 'upgraded' to an AVAST internet aware antivirus package. Deinstalling and moving to McAfee antivirus worked for about a month and then the problem reappeared. It disappeared completely and hasn't returned after many months since moving to Kaspersky antivirus.

So perhaps my problem appeared because recent antivirus software likes to monitor internet usage and tries to protect the computer from what it thinks is suspect. None of the software reported a virus or other problem. Perhaps the problem disappeared because Kaspersky does its job better.

Your problem is farly common so just bring it to the apple store and they will point you in the right direction.

Not everyone lives near an Apple store--yet.

So perhaps you would condescend to pass along the pointer or pointers in the right direction.

Steven... if you're refering to yourself, you've got 4 in the Vancouver area (downtown, Oakridge, Richmond, Burnaby).

What is the secret to fix this problem? If I bring my 3 year old iMac into the nearest Apple Store will they fix my computer while I wait? How long will it take? How much will it cost? Is it something simple I can do myself? I have tried everything posted w/o success.

However, I was also having problems with my 3 year old (original) wireless Mac Mouse losing connection. I tried everything to fix that as well and finally gave up. I bought a wired mouse and so far 3 weeks later my new wired mouse has not disconnected nor have I lost internet connection after sleep. Now I wish the iMac came w/ more USB ports.

I have no idea whether the wireless mouse losing connection and the internet lost after sleep are related.

I am still using the wireless keyboard w/o problems.

I suspect there are actually a variety problems mentioned in this thread, each with slightly different detailed symptoms but all culminating in "Internet connection lost after sleep". Having an Internet connection is actually a fairly complex process -- you need to have a physical or WiFi connection, you need to get an IP from the DHCP server, you need to get a DNS address from the router, then you need to actually be able to communicate with those servers successfully.

Therefore there is no single "the secret to fix this problem".

PS: you can pick up a USB hub pretty cheaply to get more ports. I have one with 10 powered ports.

Thanks for the heads up about the USB hub. Minor inconvenience solved. Thank you.

I seem to have this issue again.

My main problem was not Internet access specifically but accessing my NAS.

I tried the steps vpndev provided and they were helpful.

I have decided to set my iMac and WD Livebook as a static IP and manually setting the dns to point to my router. (Manual IP was not in range of norml DHCP settings BTW)

From the wake after last sleep i did the 'dig' command and Internet DNS was being picked up correctly.

My iMac also did a TimeMachine backup successfully.

All applications seem to talk to internet okay at moment.

Perhaps it's DHCP renews from wakeup or is specifically DNS?

I called Apple toninight and I was told that Apple knows about this problem and is working on a fix. There will be an update coming sooon we can hope. So we all just have to wait but at least they are working on it.

Happened to me for second time in neatly a year. Fixed it by turning off wireless to disconnect from home network then turning it back on. This was after the Lion 10.7.3 update on my mid-2011 iMac. It connects to our ISP''s router/modem wirelessly. It was also a couple of weeks after I had updated to the new Airport utility. The day prior, the utility had been open, saying there was a problem with the Time Capsule, which is wire-connected to the iMac and set up wirelessly to connect to our ISP's router within the home network. Anyway, this was the fix today in my case.

I've had the problem with a couple of iMacs -- first the 2010 which got fixed months ago and now a new 2011 whch showed the same symptoms. Both have Lion 7.3 and the default settings.

I went back through all my previous troubleshooting and notes and thought I had it fixed a couple times -- but no.

Finally, now I think I have it fixed -- after all the other iMac, except being a year older is running the exact same config on the exact same network with the same settings and O/S.

I reset all my network equipment -- first the Comcast router to the house, next the Apple base station and finally the 2 Airport Express devices I have set up to extend the network. Last, I powered off the iMac and restarted it.

It seems to be working now..not losing connection. Maybe something to do with the network refreshing the routing tables, losing the new device? Who knows.... All I know is that the other iMac has had zero problems for months -- probably after I reset the devices which I did back then for some reason.

Hope it helps.

Thanks for this information.

If Apple is working on a fix, I would infer that it's not something an ordinary user can fix at home. This problem has come, and then gone, and then come back again in my iMac, and it changes a little from time to time in what I have to do to get the connection going again.

It's a nuisance. But more than the minor annoyance and waste of time in getting the connection back up, the problem pokes a hole in my idea that the Apple OS is seamless. There's definitely an Apple problem here (and another one I have with AirTunes), and it's hard not to resent their stance that I ought to pay them $49 for support help for a system problem that was almost certainly caused by one of their tweaks to Safari or to some more esoteric part of the OS.

If they can cause a problem and then charge us when we ask for help with it, it might look to them as if they have a potentially endless source of revenue, but I doubt that it will work out that way.

Yep..I know. Even though I'm hopeful that my network reset will fix it for at least a time...I won't be surprised to see it appear again. It is ridiculous that we all have to try so many options and weird variations. It should just work.

For me, I know that the 2010 iMac on the same floor, but cloer to the base station was working fine at the same time as the other iMac wasn't. After resetting they both worked fine. Why was only the newer box losing connections? To make it even more "exciting," I have a MacAir located in the same room as the iMac which had lost its connection and it was working fine. All 3 had been updated to 10.7.3. My base station and airport express units have all been updated to the latest firmware.

C'mon Apple....fix this thing permanently.

It is true that my wife's iMac (bought at same time as mine but has not had the lost connection problem at all) is much closer to the Time Capsule than mine is, though we have two Airport Expresses spread around that should extend the range. If it's a distance-related problem, it may be hard to fix.

my wife's imac (2010) started losing it's internet connection after it was asleep. This has been happening all of a sudden this past 7-10 days. The time capsule is only 3 feet away. My macbook air in the same room has not ever experienced this problem. I was thinking of taking it into the apple store, but kinda of a hassle packing it up. I guess I'll wait the next few days and follow this forum to see if there is a fix.