Q: Mountain Lion disconnect from Ethernet in sleep mode

I agree....why put Windows on a Mac.  Also agree with the wake issue not waking the Ethernet correctly.  Seems odd that, to best of my knowledge, nobody has had issues with the wifi waking on this version.  Network switch....hmmm....I am not sure if I would say it's bad.  All my other devices have not had any issues connecting (4 windows netbook/laptop, Kindle Fire, Roko box and a few satellite TV boxes). 

Again, since I manually set my IP address...no issues.  Has been touble free since 09Oct12...about 12 days. This is not a big deal for me since I am on an iMac, but this would suck if I had a MBP.

I have been running some days now with manual speeds settings instead of autonegiotiate. So far so good. No problems anymore. Let see if it lasts more than a month...  I agree with you that other stuff runs fine on the switch so the iMac should do that too. (And it did before 10.7.2). So what did they change that causes this? I know they have changed things in powermanagement so likely something messed it up.

But what the final solution might be. Apple should solve this.

paris_slim wrote:

 

... Was surprised once by the network disconnect and no matter what I did, it required a reboot to fix this.

 

I use a manually configured IP on the ethernet connection. Wifi didn't appear to work, either though.

 

I've tried checking the "Network wakes up" box, but it looks like most haven't had success with this. Time will tell.

 

I hope this works, in which case at least I won't have to reboot:

 

ifconfig en0 down

sleep 10

ifconfig en0 up

....

Did that "permanently" fix the problem of hard-wired Ethernet connection being disconnected after wake from sleep?

And has anybody had success with the same technique without a manually configured IP?

After all this when will Apple accept there is an issue with this and atleast endeavour to solve the problem.  Come on Apple!!!

Well, I updated iPhoto last night and guess what?  Yep, my Ethernet starting dropping out again.  And I again, did the SMC reset with the safe mode start.  So far, all is stable again.  Just like the last time I updated iPhoto, why would it effect the Ethernet interface?  Apple needs to do something soon....this is sad.

kevinwschafer wrote:

 

Well, I updated iPhoto last night and guess what?  Yep, my Ethernet starting dropping out again.  And I again, did the SMC reset with the safe mode start.  So far, all is stable again.  Just like the last time I updated iPhoto, why would it effect the Ethernet interface?  Apple needs to do something soon....this is sad.

I suspect the success with SMC reset plus safe-mode start cure is just a red herring; after all, for at least some of us (many?) with the Ethernet drop after wake from sleep, merely restarting always restores the Ethernet connection. And, no matter what we try, the problem eventually and even unpredictably the problem arises once more.

Smc reset won't help because network configuration is not kept in smc.

If you have problems during live situation ( network load on it ) it also can be a cabling problem.

I never had that problem.

finally, I found the solution,

changing lease time of DHCP server, from 2hours to 1week.

I think this is the problem of compatibily beetween router and osx.

maybe, osx doesn't request again dhcp ip when he wake up,

and routher disconnect osx and loose his IP.

Did you change the DHCP settings on your Mac or on the router's settings?

And if it's on your Mac, can you explain the step by step?

I changed the router's settings.(no changing on osx.)

I hope it will works to you, too.

So you changed the 86 400 seconds into 604 800?

yes, I did. and works fine. ^^

My iMac didn't disconnect for 3 days now... But if the problem appear once again, I'll try that, thanks a lot

I posted the DHCP lease time change on August 7th

Also I changed it back as I had problems 1 or 2 times in August, For the past 2 months I had a DHCP reserved IP address in my router and no issues at all, well I had one which was fixed by ifconfig en0 down/up and I'm not sure is was related to this problem.

It's true the network configuration is NOT in SMC, but I'm sure "System Management Controller" is in charge of WOL, Mouse, Keyboard and other power events while the Mac is at sleep, it's also in charge of Powerup sequence's when a wakeup event is recieved.