Ethernet all green lights, not working

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Level 2

250 points

Ethernet all green lights, not working

Hi, all.

Yesterday I was happily using the Internet at work , connected via Ethernet cable to our network. I unplugged the cable from my mbp to allow coworker to use it and when I repluggef myself my connection no longer worked. Coworker (on a MacBook) reconnected and hers still worked fine. We have shared cable many times be fore. Tech support at work little help as they have only the mist limited tolerance for our "rogue" mac laptops.

-built in Ethernet in network preferences is a green light.
-network diagnostics keeps telling me I am connected to Internet
-ping doesn't work
- no pages load on safari or firefox
- email won't connect

Tried
-"renew dhcp lease" this has worked in past but not now
- turning apple talk on or off doesn't change things
- addded thebopen DNS address of 208.67.220.220
- turned airport off
- dragged built in ethernet to top of list
- made a new location in network preferences instead of automatic
- repaired permissions
- restarted about a million times
- switched cables, tried another port next door
- checked coworker's settings : are same as
mine (her IP address is obviously different at end)
- changed the language in international settings (lol, it seems to fix other problems, right?)

So, I've been busy and unsuccessful. Biggest clues seem to be that Network Diagnostics thinks I'm connected and says nothings wrong. And, it was working fine yesterday and ceased working midsession, and coworker's mac also running 10.5.8 works fine on same cables and ports.

Please help!! I've wasted half my day already.. Thanks in advance!

AJ

MBP & trusty iMac G4, Mac OS X (10.5.8)

Posted on Aug 19, 2009 12:44 PM

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Answer 1

aejohns Author

Level 2

250 points

Aug 19, 2009 1:38 PM in response to aejohns

I solved my own problem (finally!), but I'll post the solution here in case it helps anyone else.

I changed my IP address to that of my coworker's computer, and now it works fine (she's not here right now, lol, nor is her computer connected to the internet). When she gets back we may have to mess around a little with finding the addresses necessary to making it work for both of us. Then again, instead of always having to share the cable, we may pop for an airport and hope the tech guys don't mind!

Thanks for reading.

Amy

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Answer 2

Dogcow-Moof

Level 8

36,851 points

Aug 19, 2009 2:48 PM in response to aejohns

Please do remember to change it back.

Two computers with the same IP address can cause a great deal of network havoc.

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Answer 3

aejohns Author

Level 2

250 points

Aug 19, 2009 4:19 PM in response to aejohns

Thanks. Will defintely change it back, but here's what's happening now: when I chnage the IP address, it'll work briefly and then revert to previous mentioned issues. If I fish around for other unused IP addresses it'll work for abot a minute and then hang up. If I let it configure automatically it assisgns me IP address 10.6.32.13 which doesn't work at all. IT cannot help until tomorrow morning earliest.

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Answer 4

Dogcow-Moof

Level 8

36,851 points

Aug 19, 2009 4:42 PM in response to aejohns

Many routers used in a corporate marketplace will refuse to allow any IP addresses the router did not hand out, figuring it's someone trying to illegally use the network. That may be what you're experiencing.

However, the better question that your IT folks will need to sort out is why you can't communicate when you're assigned a perfectly valid IP address.

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Answer 5

aejohns Author

Level 2

250 points

Aug 20, 2009 5:24 PM in response to aejohns

The solution about changing the IP addresses only worked for a couple of minutes.

Here's the rest of the situation:

We can get to our own school district's website. I can see the other networked computers listed in my finder. The green lights and diagnostics say I am connected. This is affecting my coworker's mac and mine.

I try setting up my Airport Express. It too showed a happy green light while neither my coworker or I could get on the internet.

Did I mention in earlier post that I tried the open DNS thingies and I've tried typing in the numeric address for apple and neither worked?

I would be super grateful for any help. I work in a school district and there are just too few IT people for them to spend much time worrying about the problems of two Mac users. An IT person stopped by today, and she looked at a couple of things, speculated there was a firewall issue in my settings, and told me it could be the certificates. But, she didn't have any ideas on what to do, and that may be all the tech help I'll get because they're so overworked.

Finally, I don't want to seem like one of those "the-latest-update-ruined-my-happy-life people," but could this be related to the 10.5.8 update? If so, I guess it doesn't help me solve it.

Thanks again in advance.

Amy

Message was edited by: Amyjbd

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Answer 6

Dogcow-Moof

Level 8

36,851 points

Aug 21, 2009 3:13 AM in response to aejohns

It sounds like your local DHCP server is keeping track of what MAC address it assigned which IP address and isn't happy about the cable swapping that occurred.

Try obtaining a whole new IP address from DHCP by doing the following:

1) Go to your Network preferences pane
2) Click on the interface you're using (Ethernet)
3) Click the "-" button on the lower left of the list to delete the interface, then click "Apply."
4) Click the "+" button on the lower left of the list and add Ethernet back to the list.
5) Click "Apply."
6) Drag Ethernet back to the top of the list. Click "Apply" if needed.

If that doesn't work it's possible whatever router your IT department is using has "black listed" your port because it wasn't happy about the multiple machines using the same IP address.

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Answer 7

aejohns Author

Level 2

250 points

Aug 24, 2009 8:28 AM in response to Dogcow-Moof

Thanks, William. I tried that (the + and - thingy) and it didn't work. I sent an email to our IT department with everything I could think of including your suggestion about their router possibly blocking my port.

In my internet searching, I've seen a couple of people mention that they have reset the WINS (possibly in terminal?). Might this help? Do you know how I do it?

Also, would the Proxies tab have anything to do with it? Right now it's on Manual, though putting it to auto didn't seem to change anything. At the bottom of the Proxies tab there's a box that says: "Bypass proxy settings for these hosts and domains" and in the box is typed "*.local, 169.254/16" Not sure if that means anything.

I appreciate anyone's help or suggestions. I just have a fear that if I don't solve this myself or at least offer good suggestions to my IT department that I'll go a long time without working internet at work. Budget cuts, ya know?

Amy

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Answer 8

Dogcow-Moof

Level 8

36,851 points

Aug 26, 2009 2:35 PM in response to aejohns

If you have a proxy server set manually and don't need one or if you need one and don't have one set, Internet access will not work for you.

Can you check with one of the PCs and see if they have any proxies set?

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Answer 9

aejohns Author

Level 2

250 points

Aug 26, 2009 8:11 PM in response to Dogcow-Moof

Great idea--I'll go exploring on a PC tomorrow and compare settings, especially about Proxies. Meanwhile, I tried my computer at another school site in our district. I had a connection for about 3 minutes and then I suffered the same symptoms I am having in my main classroom. I think each school site has its own router, so I found this interesting.

I'm hoping Snow Leopard will magically solve all of this for me.

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Answer 10

Dogcow-Moof

Level 8

36,851 points

Aug 26, 2009 11:24 PM in response to aejohns

I suspect this is a central router or firewall in your district that's just dropping the hammer on your connection because it's not properly authorized for whatever reason.

I still suspect somewhere there's a registry that someone needs to add your machine to because it's a Mac; this is the case in many businesses that erroneously rely on Dynamic DNS/DHCP Option 81 registration from connected clients as some type of security mechanism.

I suspect this may be a matter of finding a district IT person who actually knows how your routers and DNS system are set up.

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