Browsers suddenly no connection via Ethernet!??

Question

Browsers suddenly no connection via Ethernet!??

Hi there, odd problem happening just this morning. iMac in basement office connected to AirPort upstairs via ethernet cable. Internet conneciton via browsers Safari and Firefox now suddenly inoperative. Ethernet is green-lighted in the Network preferences panel and is at the top of the list. WiFi works splendidly so no issues there.

TCP/IP results:

ConfigureIPv4: Using DHCP

IPv4 Address: 169.254.143.112

Subnet Mask: 255.255.0.0

Router: (blank)

Other than a physical break in the cable (mice?) I cannot think what could be the problem. We had thunderstoprms in the area yesterday but no lightning strikes near the house, only in the far distance. House electrics are working just fine, no other systems affected. iMac has worked flawlessly until now. Am I missing something?

iMac, Mac OS X (10.7.4)

Posted on Jul 14, 2012 1:03 PM

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Answer 1

Jul 14, 2012 1:22 PM in response to Ronald Hasler

Ron..

Try System Preferences > Network > Assist Me > Diagnostics

That may narrow down the culplrit.

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Answer 2

lynnie61

Level 1

54 points

Jul 14, 2012 3:58 PM in response to Ronald Hasler

Further from what Carolyn said, when you press diagnostics you will see about 8 things listed on the left all hopefully with green lights. If any are yellow or red, you've got an issue. Sometimes when I have a problem with airport, I do one of two things. I turn it off on the computer, count to 10 and turn it back on, or physically unplug the airport, wait a while and plug it back in. It takes about two minutes to reset. Depending in which lights are yellow/red, your provider might be the problem.

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Answer 3

Jul 14, 2012 8:27 PM in response to Carolyn Samit

Carolyn, thank you for the reply. Yes, I tried that several times before posting here, knowing enough about troubleshooting on the Mac to at least try the onbard diagnostic tools before bothering the community. The green lighted Ethernet status told me it might be some kind of odd gremlin though, as I usuallly can figure out hardware connections without to much drama.

It's back up now, all green lights on the left panel with no explanation? 😕

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Answer 4

Jul 14, 2012 8:26 PM in response to lynnie61

lynnie61 thank you also! I restarted both my cable modem and AirPort twice in effort to reset the connection. Nothing worked, I even restarted the iMac also to no avail. Only when I let it be for 30 minutes and checked later did I discover a normal coneciton. Weird. Could this be the dodgy ethernet port issue I've heard exist on some iMacs?

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Answer 5

Jul 17, 2012 2:40 AM in response to Ronald Hasler

Just a quick update. My problems are continuing with intermittant Ethernet connectivity. Connection is still unstable tho, today, I was able to reconnect by simply putting the iMac to sleep then waking. Very frustrating as I've only had this computer for seven months! 😐

Calling AppleCare tomorrow.

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Answer 6

lynnie61

Level 1

54 points

Jul 17, 2012 5:06 AM in response to Ronald Hasler

Just a thought Ronald, have you updated your airport software recently?

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Answer 7

Jul 17, 2012 11:21 AM in response to lynnie61

Lynnie61, hi. Yes, everything's up-to-date. Brand new AirPort Extreme too so I'm still scratching my head. Thanks for the follow up thought. Cheers.

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Answer 8

Jul 21, 2012 10:59 AM in response to Ronald Hasler

Hello. Updating everyone on the ethernet problem that has ... now vanished like a thief in the night!!? OK, as long as I do not shut down the iMac the ethernet Internet connection remains stable. Sleeping iMac is OK but shows "cable not connected" for a second or two, then all is well. Strange. I am thinking it might be a misbenaving AirPort base station but will continue monitoring just in case I can be of help to others. Thanks for all the replies. Cheers.

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